Engine crankshaft assembly with internal reinforcement structure

Abstract

A crankshaft assembly having an internal reinforcement structure, a method for manufacturing / using such a crankshaft assembly, and an internal combustion engine equipped with such a crankshaft assembly are provided. A crankshaft body formed of a first material includes a plurality of bearing journals coaxial with each other for rotation on the crankshaft axis and spaced apart from each other along the length of the crankshaft. Each bearing journal has an internal journal cavity. A plurality of crank pins are spaced apart from each other longitudinally and axially offset from the rotational axis of the crankshaft. Each crank pin has an internal crankpin cavity. A plurality of crank webs protrude radially from the crankshaft axis and interconnect the bearing journals and the crank pins. Each crank web has an internal web cavity. A reinforcement rod formed of a second material having an elastic modulus greater than that of the first material is disposed within the journal cavity, the crankpin cavity, and / or the web cavity.

Description

Technical Field

[0001] The present disclosure relates generally to torque-transmitting shafts. More particularly, aspects of the present disclosure relate to crankshaft assemblies for internal combustion engines. Background Art

[0002] Current production motor vehicles, such as modern automobiles, are initially equipped with a powertrain that operates to propel the vehicle and power its onboard electronics. For example, in automotive applications, the vehicle powertrain is typically represented by a prime mover that transmits drive torque to the vehicle's final drive system (e.g., differential, axles, wheels, etc.) via an automatic or manually shifted power transmission. Historically, automobiles have been powered by reciprocating piston internal combustion engine (ICE) assemblies due to their ease of use, relatively low cost, light weight, and overall efficiency. As non-limiting examples, such engines include spark-ignition (SI) gasoline engines, compression-ignition (CI) diesel engines, two-stroke, four-stroke, and six-stroke architectures, and rotary engines. Hybrid electric vehicles (HEVs) and fully electric vehicles (FEVs), on the other hand, use alternative power sources for vehicle propulsion, such as battery-powered or fuel cell-powered traction motors. By doing so, HEVs and FEVs are able to minimize or eliminate reliance on fossil fuel-based engines for traction power.

[0003] A common overhead valve internal combustion engine consists of an engine block with a series of internal cylinder bores, each housing a piston that reciprocates therein. A cylinder head, which cooperates with the pistons and cylinder bores to form combustion chambers, is coupled to the top surface of the engine block. These reciprocating pistons convert the pressure generated by the ignition of the fuel and air mixture within the combustion chambers into rotational force to drive the engine crankshaft. The cylinder head defines intake ports, through which air, supplied by the intake manifold, is selectively introduced into each combustion chamber. The cylinder head also defines exhaust ports, through which exhaust gas and combustion byproducts are selectively vented from the combustion chambers to the exhaust manifold. The exhaust manifold then collects and combines exhaust gas for metered recirculation into the intake manifold, delivery to a turbocharger that drives a turbine, or discharge from the vehicle via the exhaust system. The exhaust system incorporates a catalyst to reduce harmful pollutants such as carbon monoxide, unburned hydrocarbons, nitrogen oxides, and soot (for example, in diesel engines).

[0004] As the name suggests, a four-stroke internal combustion engine typically operates in four distinct phases, or "strokes," to drive the engine's crankshaft. During one such (first) phase of operation (called the "intake stroke"), a metered mixture of fuel and air is introduced into each cylinder as the corresponding piston travels linearly from top to bottom along the length of the cylinder bore. The engine's intake valve opens, allowing the vacuum pressure created by the downward-traveling piston to draw air into the combustion chamber. At the end of this cycle, a metered amount of finely atomized fuel is introduced into the chamber via a fuel injector. During the subsequent (second) phase (called the "compression stroke"), the intake and exhaust valves close as the piston travels upward, compressing the fuel-air mixture. After the compression stroke is complete, another (third) phase, or "power stroke," begins. The spark plug ignites the compressed fuel and air, and the resulting explosive expansion of the gases pushes the piston back to bottom dead center (BDC). During the subsequent phase (often called the "exhaust stroke"), the piston returns to top dead center (TDC) again, with the exhaust valve opening; the advancing piston expels the spent air-fuel mixture from the combustion chamber. It takes two crankshaft revolutions to complete the four strokes of a single power (Otto) cycle.

[0005] An engine's crankshaft converts the reciprocating linear motion of the engine's pistons into rotational motion, which is output as drive torque to propel the vehicle. Unlike conventional torque-transmitting shafts (manufactured with perfectly round cylinders), an engine crankshaft is a nonlinear structure with coaxial bearing journals interconnected by a series of axially offset crankpins, to which the reciprocating pistons are attached via connecting rods. These axially aligned bearing journals are spaced along the length of the crankshaft and ride on bearing bushings retained in the engine's crankcase. Radially projecting crank webs connect the bearing journals to the crankpins; optional counterweights integrated with the webs help balance internal forces or reduce loads on the main bearing journals. To reduce crankshaft mass, a hollow core can be formed within and extending through each of the crankpin and bearing journals. However, any reduction in mass must be balanced against undesirable noise, vibration, and harshness (NVH) and the crankshaft's ability to withstand the stresses associated with engine operation. Summary of the Invention

[0006] This document describes a crankshaft assembly with an internal reinforcement structure, methods for manufacturing and using such a crankshaft assembly, an internal combustion engine equipped with such a crankshaft assembly, and a motor vehicle equipped with such an engine. In a non-limiting example, an engine crankshaft assembly includes an internal reinforcement structure encapsulated within one or more of the crankpin and bearing journal of the crankshaft. The crankshaft can be cast and machined from a lower modulus material such as ductile (ductile) cast iron, while the internal reinforcement structure can be made from a higher modulus material such as steel or ceramic. The reinforcement structure can take the form of an elongated I-beam that can be twisted axially and bent transversely into a sinusoidal or spiral shape and passed through a hollow core or geometrically complementary through-holes in the bearing journal, web, and crankpin. Alternatively, one or more separate I-beam sections can be encapsulated within each crankpin / journal / web. The space between the internal reinforcement structure and the inner diameter (ID) surface of the optional hollow core of the crankpin / journal / web can be filled with nylon, plastic, rubber, aluminum, tin, or wood. To simplify manufacturing and assembly, the internal reinforcement structure may be cast or forged within a cavity within the crankshaft. Ancillary benefits of at least some disclosed concepts include a crankshaft assembly having an internal reinforcement structure that increases elastic modulus, reduces noise and vibration, and reduces material costs.

[0007] Various aspects of the present disclosure relate to internally reinforced crankshaft assemblies for use in torque-generating devices (e.g., ICE components), pressure-generating devices (e.g., compressors and pumps), and other vehicular and non-vehicular applications. For example, a representative crankshaft assembly includes a crankshaft body formed entirely or partially from a rigid (first) material. The crankshaft assembly includes a plurality of bearing journals, a plurality of crankpins, and a plurality of crank webs. The bearing journals are coaxial with one another for rotation on the crankshaft axis and are spaced apart from one another along the length of the crankshaft body. The crankpins are also spaced apart from one another along the length of the crankshaft body; however, the crankpins are axially offset from the crankshaft axis. The crank webs project radially from the crankshaft axis and interconnect the bearing journals and crankpins. Each bearing journal, crankpin, and crank web defines a corresponding cavity therein. One or more reinforcement rods are disposed within one or more, or all, of the journal, crankpin, and / or web cavities. Each reinforcement rod is formed entirely or partially from another rigid (second) material having an elastic modulus greater than that of the first material.

[0008] Additional aspects of the present disclosure relate to a motor vehicle equipped with an internal combustion engine having a crankshaft assembly with an internal reinforcement structure. As used herein, the terms "vehicle" and "motor vehicle" are used interchangeably and synonymously to include any relevant vehicle platform, including but not limited to passenger vehicles (ICE, HEV, FCH, fully and partially autonomous vehicles, etc.), commercial vehicles, industrial vehicles, tracked vehicles, off-road and all-terrain vehicles (ATVs), motorcycles, agricultural and construction equipment, watercraft, aircraft, etc. In one example, the motor vehicle includes a vehicle body with a passenger compartment, a plurality of wheels rotatably mounted to the vehicle body (e.g., via a unibody chassis or a body-on-frame chassis), and other standard original equipment. An engine assembly is also mounted to the vehicle body and operates alone (e.g., for an ICE powertrain) or in combination with one or more electric traction motors (e.g., for a hybrid electric powertrain) to selectively drive one or more wheels to thereby propel the vehicle.

[0009] Continuing with the discussion of the above example, an engine assembly includes an engine block having a series of internal cylinder bores, a piston reciprocatable within each cylinder bore, and a crankshaft assembly, for example, located in a crankcase of the engine block. The crankshaft assembly includes a single-piece crankshaft body formed in whole or in part from a rigid (first) material. The crankshaft body includes two or more bearing journals rotatably attached to the engine block, coaxially arranged to rotate about the crankshaft's central axis, and spaced apart from one another along the length of the crankshaft body. Each bearing journal defines a journal cavity therethrough. A series of crankpins are coupled to the pistons, spaced apart from one another along the length of the crankshaft body, and axially offset from the crankshaft's central axis to orbit about the crankshaft axis. Each crankpin defines a crankpin cavity therethrough. A crank web projects radially from the crankshaft axis and connects the bearing journal to the crankpin. Each crank web defines a web cavity therethrough. A reinforcement member having an elongated, nonlinear beam body can bend laterally (i.e., bend about a transverse axis) and rotate circumferentially (i.e., twist about a longitudinal axis) relative to a central axis of the reinforcement member such that the reinforcement member passes through a journal cavity, a crankpin cavity, and a web cavity. The reinforcement member is formed, in whole or in part, of a high-rigidity (second) material different from the crankshaft material and having a corresponding elastic modulus greater than the elastic modulus of the crankshaft body material.

[0010] Other aspects of the present disclosure relate to manufacturing processes, control logic, and computer-readable media (CRMs) for manufacturing or using any disclosed crankshaft assembly, internal combustion engine, and / or motor vehicle. In one example, a method for manufacturing a crankshaft assembly is provided. The representative method, in any order and in any combination with any of the options and features disclosed above and below, includes forming a crankshaft body from a first material, the crankshaft body comprising: a plurality of bearing journal shafts coaxial with one another for rotation on a crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therein; a plurality of crankpins spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis, each crankpin defining a crankpin cavity therein; and a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journals and crankpins, each crank web defining a web cavity therein; and positioning a reinforcement rod in one or more of the journal cavity, the crankpin cavity, and / or the web cavity, the reinforcement rod formed from a second material having a second elastic modulus greater than a first elastic modulus of the first material.

[0011] For any of the disclosed crankshaft assemblies, vehicles, and methods, the internal reinforcement rod may include or may consist essentially of an I-beam reinforcement having an I-shaped cross-section, represented by a vertical stem connecting a horizontal lower leg to a horizontal upper arm. In this case, the opposing lateral ends of the leg and arm may have rounded edges. The I-beam reinforcement may also include tracks to increase inertia that extend along the length of the beam and project laterally from the top and bottom sides of the beam. When viewed in cross-section, these tracks appear as a first circular protrusion projecting radially from the center of the outer diameter (OD) surface of the leg and a second circular protrusion projecting radially from the center of the OD surface of the arm. As yet another option, the arm and leg may share a vertical (first) thickness, with the stem having a horizontal (second) thickness that is less than the leg / arm thickness.

[0012] For any of the disclosed crankshaft assemblies, vehicles, and methods, a noise and vibration-reducing filler material may be filled into the journal, crankpin, and / or web cavities. This filler material is positioned between the internal reinforcement rod and the ID surfaces of the bearing journal, crankpin, and / or crank web housing the reinforcement rod. As a further option, the interfacial surface of the reinforcement rod contacting the ID surfaces of the journal, crankpin, and / or web cavities may be coated, machined, or surface-treated to include a surface texture designed to enhance mechanical adhesion between the reinforcement rod and the crankshaft body. It may be desirable for the crankshaft body, including the bearing journal, crankpin, and crank web, to be integrally formed as a single-piece, unitary structure. Alternatively, the crankshaft (first) material may include aluminum, an aluminum alloy, steel, or ductile iron; in contrast, the reinforcement rod (second) material may include steel, a steel alloy, or ceramic. For ceramic-based internal reinforcements, a predetermined number of discrete ceramic rods (e.g., 4-20) having a circular or polygonal cross-section may be bundled together and encapsulated within the crankshaft body.

[0013] For any of the disclosed crankshaft assemblies, vehicles, and methods, the reinforcement rod can include an I-beam reinforcement having an elongated, nonlinear, single-piece body extending end-to-end from the crankshaft body, passing through the journal cavity, crankpin cavity, and web cavity. Because the crankpin is axially offset from the bearing journal, and in some applications, circumferentially offset from each other, the I-beam body is twisted—bent laterally and rotated circumferentially—to allow the I-beam reinforcement to pass through the journal, crankpin, and web cavity. Alternatively, the reinforcement rod can include a plurality of discrete reinforcement rods, each mounted within a respective one of the journal, crankpin, and / or web cavity. Each discrete reinforcement rod is locked within a hollow core of a respective journal / crankpin / web cavity and protrudes from opposing open ends of the hollow core.

[0014] Solution 1. A crankshaft assembly comprising:

[0015] A crankshaft body formed of a first material and comprising:

[0016] a plurality of bearing journals coaxial with one another for rotation on the crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therein;

[0017] a plurality of crankpins spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis, each crankpin defining a crankpin cavity therein; and

[0018] a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journal and the crank pin, each crank web defining a web cavity therein; and

[0019] A reinforcing rod is disposed in one or more of the journal cavity, the crankpin cavity, and / or the web cavity, the reinforcing rod being formed of a second material having a second elastic modulus greater than a first elastic modulus of the first material.

[0020] Option 2. The crankshaft assembly of Option 1, wherein the reinforcement rod comprises an I-beam reinforcement having an I-shaped cross-section with a stem connecting the legs and the arms.

[0021] Option 3. The crankshaft assembly of Option 2, wherein each of the legs and arms includes a pair of corresponding opposing lateral ends having rounded edges.

[0022] Option 4. The crankshaft assembly of Option 2, wherein the I-shaped cross-section further comprises a first circular protrusion radially projecting from an outer diameter (OD) surface of the leg and a second circular protrusion radially projecting from an OD surface of the arm.

[0023] Option 5. The crankshaft assembly of Option 2, wherein the arms and legs have a first thickness and the stem has a second thickness that is less than the first thickness.

[0024] Solution 6. The crankshaft assembly according to Solution 1 further includes a filler material, the filler material being disposed in the journal cavity, the crankpin cavity, and / or the web cavity and interposed between the reinforcing rod and the bearing journal, the crankpin, and / or the crank web.

[0025] Option 7. The crankshaft assembly of Option 1, wherein the reinforcement rod includes an interface surface where the reinforcement rod contacts an inner diameter (ID) surface of the journal cavity, the crankpin cavity, and / or the web cavity, the interface surface having a surface texture configured to increase mechanical adhesion between the reinforcement rod and the crankshaft body.

[0026] Option 8. The crankshaft assembly of Option 1, wherein the reinforcement rod comprises an I-beam reinforcement having an elongated nonlinear beam body extending through the journal cavity, the crankpin cavity, and the web cavity.

[0027] Option 9. The crankshaft assembly according to Option 8, wherein the beam body of the I-beam reinforcement is laterally bent and circumferentially rotated relative to the central axis of the I-beam reinforcement.

[0028] Option 10. The crankshaft assembly of Option 1, wherein the reinforcement rod comprises a plurality of discrete reinforcement rods, each reinforcement rod being mounted within a respective one of the journal cavity, the crankpin cavity, and / or the web cavity.

[0029] Option 11. A crankshaft assembly according to Option 10, wherein each of the journal cavity, crankpin cavity and web cavity includes a through hole having a hollow core with opposing open ends, and wherein each discrete reinforcement rod is located within a corresponding one of the hollow cores and protrudes from the open end of the hollow core.

[0030] Option 12. The crankshaft assembly of Option 1, wherein the first material comprises aluminum, an aluminum alloy, or ductile iron, and wherein the second material comprises steel, a steel alloy, or ceramic.

[0031] Option 13. The crankshaft assembly of Option 1, wherein the crankshaft body, including the bearing journal, crank pin, and crank web, is integrally formed as a single-piece structure.

[0032] Solution 14. A motor vehicle comprising:

[0033] vehicle body;

[0034] a plurality of wheels rotatably attached to the vehicle body; and

[0035] An internal combustion engine (ICE) assembly attached to a vehicle body and operable to output engine torque to one or more of the wheels, thereby propelling the motor vehicle, the ICE assembly having an engine block defining a plurality of cylinder bores, a plurality of pistons each reciprocally movable within a respective one of the cylinder bores, and a crankshaft assembly, the crankshaft assembly comprising:

[0036] A single-piece crankshaft body formed of a first material and comprising:

[0037] a plurality of bearing journals rotatably attached to the engine block, coaxial with one another for rotation on the crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therethrough;

[0038] a plurality of crankpins, each coupled to a respective one of the pistons, spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis for orbital rotation about the crankshaft axis, each crankpin defining a crankpin cavity therethrough; and

[0039] a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journal and the crank pin, each crank web defining a web cavity therethrough; and

[0040] An I-beam reinforcement has an elongated nonlinear beam body that bends laterally and rotates circumferentially relative to a central axis of the I-beam reinforcement, the I-beam reinforcement extending through a journal cavity, a crankpin cavity, and a web cavity, the I-beam reinforcement being formed of a second material having a second elastic modulus greater than a first elastic modulus of the first material.

[0041] Solution 15. A method of manufacturing a crankshaft assembly, the method comprising:

[0042] A crankshaft body is formed from a first material, the crankshaft body comprising:

[0043] a plurality of bearing journals coaxial with one another for rotation on the crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therein;

[0044] a plurality of crankpins spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis, each crankpin defining a crankpin cavity therein; and

[0045] a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journal and the crank pin, each crank web defining a web cavity therein; and

[0046] A reinforcing rod is positioned within one or more of the journal cavity, the crankpin cavity, and / or the web cavity, the reinforcing rod being formed of a second material having a second elastic modulus greater than a first elastic modulus of the first material.

[0047] Option 16. The method according to Option 15, wherein the reinforcement bar includes an I-beam reinforcement having an I-shaped cross-section, the I-shaped cross-section having a stem connecting the legs and the arms.

[0048] Embodiment 17. The method of embodiment 16, wherein each of the legs and arms includes a pair of corresponding opposing lateral ends having rounded edges.

[0049] Option 18. The method of option 16, wherein the I-shaped cross-section further comprises a first circular protrusion radially protruding from an outer diameter (OD) surface of the leg and a second circular protrusion radially protruding from the OD surface of the arm.

[0050] Option 19. The method of Option 15 further comprises: adding a filler material into the journal cavity, the crankpin cavity, and / or the web cavity and placing it between the reinforcing rod and the bearing journal, the crankpin, and / or the crank web.

[0051] Option 20. A method according to Option 15, wherein the reinforcement rod includes an I-beam reinforcement having a slender nonlinear beam body extending through the journal cavity, the crankpin cavity and the web cavity, wherein the beam body bends laterally and rotates circumferentially relative to the crankshaft axis.

[0052] The above summary of the invention does not represent every embodiment or every aspect of the present disclosure. Instead, the above-mentioned features and advantages of the present disclosure, as well as other features and attendant advantages, will be readily apparent from the following detailed description of illustrative examples and modes for implementing the present disclosure when taken in conjunction with the accompanying drawings and the appended claims. Furthermore, the present disclosure expressly includes any and all combinations and subcombinations of the elements and features described above and below. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 is a front perspective view of a representative motor vehicle with an inset schematic illustration of a representative reciprocating piston internal combustion engine assembly with an engine crankshaft having internal reinforcement structures in accordance with aspects of the present disclosure.

[0054] Figure 2 is a side view of a representative engine crankshaft assembly having an I-beam core reinforcement according to aspects of the present disclosure.

[0055] Figure 3 is a perspective view of a portion of another representative engine crankshaft assembly having discretely packaged I-beam core reinforcements in accordance with aspects of the disclosed concept.

[0056] Figure 4 is a perspective view of a portion of yet another representative engine crankshaft assembly having an internally encapsulated torsional I-beam core reinforcement in accordance with aspects of the disclosed concept.

[0057] Representative embodiments of the present disclosure are shown in the accompanying drawings by way of non-limiting example and are described below in additional detail. However, it should be understood that the novel aspects of the present disclosure are not limited to the specific forms shown in the accompanying drawings listed above. On the contrary, the present disclosure is intended to cover all modifications, equivalents, combinations, sub-combinations, permutations, groupings, and substitutions falling within the scope of the present disclosure, such as those encompassed by the appended claims. DETAILED DESCRIPTION

[0058] The present disclosure allows for embodiments in many different forms. Representative examples of the present disclosure are shown in the accompanying drawings and are described in detail herein with the understanding that these embodiments are provided as illustrations of the disclosed principles and not as limitations on the broad aspects of the present disclosure. To this end, elements and limitations that are described in the "Abstract," "Technical Field," "Background," "Summary," "Brief Description of the Drawings," and "Detailed Description" sections but not expressly set forth in the claims should not be incorporated into the claims, either individually or collectively, by implication, inference, or otherwise. In addition, the drawings discussed herein may not be drawn to scale and are provided for guidance purposes only. Therefore, the specific and relative dimensions shown in the drawings should not be interpreted as limiting.

[0059] For purposes of this detailed description, unless otherwise stated: the singular includes the plural and vice versa; the terms "and" and "or" shall be both conjunctions and disjunctive conjunctions; the terms "any" and "all" shall both mean "any and all"; and the terms "including," "comprising," "containing," "having," and their permutations shall each mean "including but not limited to." In addition, approximate terms such as "about," "almost," "substantially," "approximately," and the like may each be used herein in a sense such as, for example, "at, approximately, or nearly at," or "within 0-5% of," or "within acceptable manufacturing tolerances," or any logical combination thereof. Finally, directional adjectives and adverbs such as head, tail, inboard, outboard, starboard, port, vertical, horizontal, up, down, front, rear, left, right, and the like may refer to a motor vehicle when the vehicle is operatively oriented on a level driving surface, e.g., relative to the forward direction of travel of the motor vehicle.

[0060] Referring now to the drawings, wherein like reference numerals represent like features throughout the several views, Figure 1 A perspective view of a representative automobile is shown in the figure, which is generally indicated at 10 and is depicted as an engine-propelled sedan-type passenger vehicle for the purposes of discussion herein. The illustrated automobile 10, also referred to herein as a "motor vehicle" or simply as a "vehicle," is merely an exemplary application with which the novel aspects of the present disclosure may be practiced. Similarly, the implementation of the present concepts in a gasoline engine should also be understood as an exemplary application of the novel concepts disclosed herein. As such, it will be understood that the features of the present disclosure may be applied to other engine configurations, implemented by alternative powertrain architectures, and used in any logically related vehicular and non-vehicular applications. Finally, only selected components of the automobile and internal combustion engine are shown and will be described herein in additional detail. Nevertheless, the vehicles and engines discussed below may include many additional and alternative features, as well as other available peripheral components for performing the various methods and functions of the present disclosure.

[0061] Figure 1An example of a twin-cam inline engine assembly 12 is shown mounted within an engine compartment 14 of a vehicle body. The illustrated engine assembly 12 is a four-stroke reciprocating piston engine configuration that operates to propel the vehicle 10, for example, as a direct injection (DI) gasoline engine, including its flexible-fuel vehicle (FFV) and hybrid electric vehicle (HEV) variants. The engine assembly 12 can optionally operate in any of a variety of selectable combustion modes, including a homogeneous charge compression ignition (HCCI) combustion mode and an adjustable-lift spark ignition (SI) combustion mode. Although not explicitly depicted in FIG1 , it is contemplated that the vehicle drivetrain can employ any available configuration, including a front-wheel drive (FWD) layout, a rear-wheel drive (RWD) layout, an all-wheel drive (AWD) layout, a four-wheel drive (4WD) layout, and the like.

[0062] The engine assembly 12 employs a series of reciprocating pistons 16 that slidably move within cylinder bores 15 of the engine block 13. The engine pistons 16 are typically provided in even numbers of 4, 6, 8, etc., and are arranged in a V- or I-type configuration. The top surface of each piston 16 cooperates with the inner periphery of its corresponding cylinder 15 and the corresponding chamber surface 19 of the cylinder head 25 to define a variable volume combustion chamber 17. Each piston 16 is connected to the crankpin ( Figure 2 ). Crankshaft 11, in turn, converts the linear reciprocating motion of piston 16 into rotational motion, which is output, for example, as revolutions per minute (RPM) to a power transmission (not shown) to drive one or more wheels 22. Crankshaft 11 is shown enclosed within a crankcase 23 mounted below engine block 13. Although shown as separate components, engine block 13 and cylinder head 25 may be integrally formed as a single-piece, unitary, "monolithic" structure.

[0063] The air intake system delivers intake air to cylinders 15 via intake manifold 29, which directs and distributes the air into combustion chambers 17 via intake runners in cylinder head 25. The engine's air intake system includes an airflow ductwork system and various electronic devices for monitoring and regulating the incoming air flow. As a non-limiting example, the air intake device may include a mass air flow sensor 32 for monitoring mass air flow (MAF) 53 and intake air temperature (IAT) 55. A throttle valve 34 controls air flow to engine assembly 12 in response to a control signal (ETC) 57 from a programmable engine control unit (ECU) 5. A pressure sensor 36 in intake manifold 29 monitors, for example, manifold absolute pressure (MAP) 59 and barometric pressure.

[0064] An optional external flow passage (not shown) recirculates exhaust gas from the engine exhaust to the intake manifold 29, with an exhaust gas recirculation (EGR) valve 38 used to meter the volume of recirculated exhaust gas directed back into the cylinders 15. The programmable engine control unit 5 controls the exhaust mass flow to the intake manifold 29 by controlling the opening / closing of the EGR valve 38 via an EGR command 61. Figure 1 , the arrows connecting the ECU 5 with the various components of the engine assembly 12 represent electronic signals or other communications exchanges that transmit data and / or control commands from one component to another.

[0065] Air flow from the intake manifold 29 into the combustion chamber 17 is controlled by one or more intake engine valves 20. Exhaust gas discharge from the combustion chamber 17 to the exhaust manifold 39 is controlled by one or more exhaust engine valves 18. These engine valves 18, 20 are shown herein as spring-biased poppet valves; however, other commercially available types of engine valves may be used. The valvetrain system of the representative engine assembly 12 is equipped to control and regulate the opening and closing of the exhaust and intake engine valves 18, 20. Although shown with a single pair of engine valves, it should be understood that each cylinder 15 may be equipped with multiple pairs of intake / exhaust engine valves.

[0066] Actuation of the engine valves 18 and 20 can be adjusted by controlling exhaust and intake variable cam phasing / variable lift control (VCP / VLC) devices 46 and 48. These VCP / VLC devices 46 and 48 are operable to control an intake camshaft 47 and an exhaust camshaft 49. The rotation of the intake and exhaust camshafts 47 and 49 is correlated and indexed with the rotation of the crankshaft, thereby correlating the opening and closing of the intake and exhaust valves 20 and 18 with the position of the crankshaft 11 and piston 16. The intake VCP / VLC device 46 can variably switch and control the valve lift of the intake valve 20 in response to a control signal (iVLC) 63, and variably adjust and control the phase of the intake camshaft 47 for each cylinder 15 in response to a control signal (iVCP) 65. The exhaust VCP / VLC device 48 may variably switch and control the valve lift of the exhaust valve 18 in response to a control signal (eVLC) 67 and variably adjust and control the phase of the exhaust camshaft 49 of each cylinder 15 in response to a control signal (eVCP) 69 .

[0067] Continue to refer Figure 1In a representative configuration, engine assembly 12 employs a DI fuel injection subsystem with multiple high-pressure electronic fuel injectors 28 that inject fuel pulses directly into combustion chamber 17. As shown, each cylinder 15 is provided with one or more fuel injectors 28, which are actuated in response to an injector pulse width command (INJ_PW) 75 from ECU 5. These fuel injectors 28 are supplied with pressurized fuel by the fuel distribution system. When actuated, fuel injectors 28 are operable to inject multiple fuel pulses per operating combustion cycle into a corresponding one of the engine cylinders 15. Engine assembly 12 employs either a compression ignition (for diesel engine architectures) or a spark ignition (for gasoline engine architectures), by which fuel combustion initiating energy, such as a sudden electrical discharge provided by spark plug 26 in response to spark command (IGN) 71, ignites the cylinder charge in combustion chamber 17. Fuel injectors 28 may also take the form of an electronically controlled common rail fuel injector architecture that operates in a normally closed solenoid-actuated mode of operation.

[0068] The engine assembly 12 is equipped with various sensing devices for monitoring engine operation, including a crank sensor 42 that monitors the rotational position of the crankshaft and outputs a crank angle / speed (RPM) signal 43. A temperature sensor 44 monitors, for example, one or more engine-related temperatures (e.g., coolant temperature, oil temperature, etc.) and outputs a signal 45 indicative thereof. An in-cylinder combustion sensor 30 monitors combustion-related variables such as in-cylinder combustion pressure, charge temperature, fuel mass, air-fuel ratio, etc., and outputs a signal 31 indicative thereof. An exhaust gas sensor 40 monitors one or more exhaust-related variables such as actual air / fuel ratio (AFR), burned gas fraction, etc., and outputs a signal 73 indicative thereof.

[0069] During operation of an engine assembly, the crankshaft may be subjected to significant stresses, including torsional stresses resulting from high-speed axial rotation, bending and axial stresses resulting from load variations caused by the cylinder and connecting rod firing forces, and shear forces resulting from the compressive forces generated by the combustion cycle. While it is generally desirable to reduce the weight and material cost of the crankshaft to achieve both engine / vehicle weight and cost savings, any such reduction must be balanced against the crankshaft's ability to withstand the stresses associated with engine operation. Discussed below are crankshaft assembly configurations that provide reduced weight and material cost while improving noise and vibration attenuation and increasing stress performance.

[0070] Figures 2-4 illustrate a representative crankshaft assembly with an internal reinforcement structure. The internal reinforcement structure increases the assembly's elastic modulus and helps attenuate engine-borne noise and vibration transmitted through the assembly. The reinforcement structure is constructed from a high-modulus material, such as steel, which can be cast or forged and then placed within the lower-modulus material, such as ductile iron, of the crankshaft body. The steel reinforcement structure can be extruded or rolled from bar stock, or it can be cast, forged, or stamped. Alternatively, the high-modulus material can be a ceramic or other brittle material that is difficult to machine; in this case, the softer, ductile material of the crankshaft body, such as ductile iron, can be formed around the higher-modulus, more rigid material. The contact surfaces between the crankshaft body and the internal reinforcement may be ground, shot blasted, sandblasted, chemically etched, or otherwise treated to provide a "spiny-lock" surface that helps improve mechanical adhesion between the two structures.

[0071] The geometry of the reinforcement core can be optimized to minimize variations in the gate within the metal mold; in this example, the steel structure can act like a casting chill, promoting undesirable solidification in one or more sections of the metal mold. Internal reinforcement structures can employ tubular geometries, for example, to avoid drilling unnecessary additional oil holes. This can allow for taps to be made at predetermined "optimal" locations, for example, with circular taps rather than elliptical taps (e.g., drilling a short hole per crankpin and main journal). Compared to relatively expensive and heavy all-steel crankshafts, composite crankshaft assemblies formed from cheaper and lighter ductile iron and reinforced with steel or ceramic internal reinforcements offer comparable stiffness and stress capacity without the attendant weight and cost. Internal reinforcement structures can be strategically located within the crankshaft body and can employ optimized design geometry to achieve the most effective reinforcement characteristics at the lowest manufacturing cost.

[0072] Next go to Figure 2 , shows a representative crankshaft assembly 111 having an internal reinforcement structure 160 for improving stress, noise and vibration performance. The crankshaft assembly 111 may be for vehicle applications (e.g. Figure 1 The crankshaft 11 in the engine assembly 12 of the vehicle) and non-vehicle applications (such as reciprocating compressors, oil well pumps, etc.). Although different in appearance, it is envisioned that the following reference Figure 2 Any features and options described for the crankshaft assembly 111 may be incorporated individually or in any combination into Figure 3 and 4 For example, the crankshaft assembly 111 includes an elongated nonlinear crankshaft body 150 extending along a central crankshaft axis A. CR Extending, the crankshaft assembly 111 is on the central crankshaft axis A CRThe crankshaft body 150 is generally defined by a series of main bearing journals 152, a series of crank pins (or "rod bearing journals") 154 interleaved with the bearing journals 152, a series of crank webs (or "arms") 156 interconnecting the bearing journals 152 and the crank pins 154, and an optional set of counterweights 158 coupled to or integrally formed with selected crank webs 156. As shown, the crankshaft body 111, including the bearing journals 152, crank pins 154, and crank webs 156, is integrally formed as a single-piece, unitary structure.

[0073] The main bearing journals 152 are coaxially aligned with each other and are each aligned with the crankshaft axis A CR Concentric. On the crankshaft axis A CR During rotation, the main bearing journal 152 may ride on a complementary bearing bushing (not shown) held within the engine crankcase of an internal combustion engine assembly (e.g., Figure 1 In the crankcase 23). Figure 2 Five main bearing journals 152 are shown as cylindrical structures that share a common width and diameter and are spaced apart from one another along the longitudinal length of the crankshaft body 150. Each bearing journal 152 may have a hollow structure with an internal journal cavity 151 extending axially through the center of the bearing journal 152. In particular, each optional journal cavity 151 may extend completely through the corresponding main bearing journal 152, with axially spaced cavity openings on both the engine-side (first) axial face and the transmission-side (second) face of the journal 152. Alternative configurations may include more or fewer than five main bearing journals, main bearing journals having similar or different structures than those shown, and main bearing journals with or without internal cavities or with countersunk cavities.

[0074] Continue to refer Figure 2 The crankshaft assembly 111 is particularly suitable for an inline four cylinder (I4) engine and thus includes four crank pins 154, eight connecting arms 156 and four counterweights 158. Each crank pin 154 supports a rod bearing (e.g., a plain bearing housing) thereon and serves as a piston connecting rod (e.g., Figure 1 The connecting rod 21 of the crankshaft assembly 111 attaches the piston (e.g., engine piston 16) to the attachment point of the crankshaft assembly 111. Similar to the main bearing journals 152, the crank pins 154 are spaced apart from each other along the longitudinal length of the crankshaft body 150. Unlike the bearing journals 152, the crank pins 154 are aligned with the crankshaft axis A. CR Instead, the centerline of each crank pin 154 is from the crankshaft axis A CR Radially spaced (ie, "axially offset") such that the crank pin 154 is radially spaced (ie, "axially offset") about the crankshaft axis A during rotation of the assembly 111. CRAs used herein, the term "cavity" may be used to refer to any type of structural void, including through-holes, countersunk holes, cylindrical hollow cores, concave cavities, geometrically complementary holes, centerlines, and axially offset cores, among others.

[0075] Each crankpin 154 can be structurally identical, sharing a common cylindrical structure with a hollow core defined by an internal crankpin cavity 153 extending axially through the center of the crankpin 154. Specifically, each optional crankpin cavity 153 can extend completely through the corresponding crankpin 154, having one cavity opening on the engine-side (first) axial face of the crankpin 154 and another cavity opening on the transmission-side (second) axial face. The crankshaft body 150 can include more or fewer than four rod bearing journals, can include rod bearing journals of similar or different construction than shown, and can include rod bearing journals with or without internal cavities. To this end, the crankshaft assembly 111 can be configured for other engine styles and architectures, including alternative single-bank inline layouts, multiple-bank (V) layouts, V- and I-type engines with six, eight, ten, and so on, cylinders, or inline and rotary engines with three, five, seven, and so on, cylinders.

[0076] A series of crank webs 156 physically connect the main bearing journal 152 to the crank pin 154. The crank webs 156 are interleaved with and sandwiched between the journal 152 and the crank pin 154. Each crank web 156 is a cam extending from the crankshaft axis A. CR An elliptical structure projects radially outward and extends from the bearing journal 152 to the crank pin 154. These crank webs 156 can be identical in structure to one another, or alternatively, a subset of the crank webs 156 can share one mating structure, while another subset of the crank webs 156 can share a different mating structure. As yet another option, all eight crank webs 156 and their corresponding crank pins 154 can be aligned along a single plane; otherwise, the crank pins 154 and crank webs 156 can be arranged in multiple planes, thus, about the crankshaft axis A. CR Circumferentially spaced. Figure 2 In the crankshaft body 150 , the crank web 156 covers the open end facing the journal cavity 151 and all open ends of the web cavity 155 .

[0077] An internal web cavity 155 extending through the crank web 156 connects the internal journal cavity 151 of the main bearing journal 152 and the internal crankpin cavity 153 of the crankpin 154. Similar to the journal and crankpin cavities 151, 153, each optional web cavity 155 can extend completely through the corresponding crank web 156, with axially opposing cavity openings located on the engine side (first) and transmission side (second) faces of the crank web 156. CR The centerline "origin" axis) is different from the centerline "origin" axis) of the internal web cavity 155 relative to the crankshaft axis A CR Obliquely angled and having a varying cross-section that varies along the length of the crankshaft body 150 .

[0078] To help alleviate the torsional and shear forces acting on the main bearing journals 152, thereby improving the operational life of the crankshaft support bearings, a set of counterweights 158 may be attached to the crankshaft body 150 and spaced away from the crankshaft axis A. CR Extending radially. As shown, each counterweight is a semicircular structure integrally formed with a corresponding crank web 156, projecting from the crankshaft body 150 on the side of the crankshaft body 150 opposite the web 156 and its mating crankpin 154. These counterweights 158 help offset the reciprocating mass of the piston, piston rings, piston pin, retaining clip, and upper portion of the connecting rod, as well as the rotating mass of the lower portion of the connecting rod, bearings, and crankshaft assembly 111. While the crank web 156 is the structural member of the crankshaft body 150 that physically connects the main and rod bearing journals, and the counterweights 158 can be designed to reduce bearing loads and balance engine vibrations, the crankshaft body 150 can have any number of counterweight structures attached to various sections in any combination.

[0079] An internal reinforcement structure 160 (also referred to herein as a "reinforcement rod," in the form of a rigid and contoured beam) structurally reinforces the crankshaft assembly 111 of FIG. 2 , passes through one or more or all of the journal, crankpin, and web cavities 151 , 153 , 155 , and is permanently attached to the crankshaft body 150 . As mentioned above, the crankshaft body 150 is manufactured from a rigid material having a relatively low cost, weight, and elastic modulus, while the reinforcement structure 160 is manufactured from a different rigid material having a relatively high elastic modulus (greater than the elastic modulus of the crankshaft body 150 ). For example, the crankshaft body 150 may be formed, in whole or in part, from aluminum, an aluminum alloy, titanium, or ductile iron; conversely, the reinforcement structure 160 may be formed, in whole or in part, from steel, a steel alloy, or a ceramic (such as silicon nitride, silicon carbide, or zirconium oxide). In a more specific example, Figure 2The crankshaft body 150 is forged or cast from ductile "ductile" cast iron having an elastic modulus (E) of at least 120 GPa, or in some applications, about 130 to about 170 GPa. The reinforcement structure 160, on the other hand, is hot-formed, extruded, or cast from carbon steel having an elastic modulus of at least 180 GPa, or in some applications, about 200-240 GPa. The reinforcement structure 160 may also be formed from a ceramic material having an elastic modulus of about 300-400 GPa. As will be described below, Figure 3 and 4 As described in the discussion of FIG, the reinforcement structure 160 may take on different shapes, sizes, locations, and material combinations within the contemplated scope of the present disclosure.

[0080] The packaging and design of the internal reinforcement structure 160 can be designed to simplify the manufacture of the crankshaft assembly 111 while optimizing the elastic deformation characteristics of the assembly 111. According to the illustrated example, the reinforcement structure 160 is a non-linear, single-piece structure that is almost entirely located within the crankshaft body 150, with only negligible sections at its opposite ends protruding from the longitudinal ends of the crankshaft body 150. Figure 2 As best seen in the cross-sectional view presented in the inset of FIG, the representative reinforcement structure 160 takes the form of an elongated I-beam reinforcement that extends diametrically across the internal cavities 151, 153, 155 within the bearing journal 152, crank pin 154, and crank web 156 and contacts the ID surface of the crankshaft body 150. Using this structure, the reinforcement structure 160 is immovably and securely mounted within the crankshaft body 150. As mentioned above, the cavities 151, 153, 155 can be cylindrical through-holes or can be through-holes of complementary geometry, substantially identical to the geometry of the reinforcement structure 160.

[0081] Figure 2 The reinforcement structure 160 has an I-shaped cross-section, characterized by a vertical stem 161 interconnected with a horizontal lower leg 163 and a horizontal upper arm 165. The opposite lateral ends of the legs 163 and arms 165 can be square (e.g., to simplify design and manufacturing), pointed ( Figure 2 ) (for example, to locate the contact of the shaft with the reinforcement), or may have rounded edges ( Figure 3 ) (e.g., to provide flush contact between the reinforcement structure 160 and the crankshaft body 150 when formed with a hollow core). Projecting vertically downward and upward from the bottom and top sides of the I-beam reinforcement 160, respectively, are a pair of optional inertia increasing rails 167 and 169, which can extend along the entire longitudinal length of the I-beam reinforcement 160. When viewed in cross section, these rails 167, 169 appear as breadcrumb-shaped protrusions ( Figure 2 ) or semicircular protrusions ( Figure 3 and4 ), each of which has a circular contact surface and projects radially from the center of the OD surface of the leg 163 or arm 165. It is contemplated that the reinforcement structure 160 may take on geometries, sizes, and orientations alternative to those shown in the figures.

[0082] To aid castability while maximizing rigidity and reducing mass, the arms 163 and legs 165 may share a vertical (first) thickness T l , and the stem 161 may have a thickness less than the first thickness T l In at least some embodiments, the vertical thickness T1 of the legs and arms 163, 165 is about 10 mm to about 15 mm, while the horizontal thickness T2 of the stem 161 is about 5 mm to about 8 mm. In this example, the wall thickness T3 of the crankshaft body 150 can be about 3 mm to about 6 mm, resulting in the crankshaft body 150 having an OD surface diameter of about 46 mm to about 52 mm. Alternatively, the thicknesses T1 and T2 of the legs / arms and stem can be substantially the same.

[0083] An optional filler material 162, such as polymer foam, tin, aluminum, nylon, or a suitable material with a high melting point, may be disposed within the journal, crankpin, and / or web cavities 151, 153, 155 and between the reinforcing rod 160 and the ID surfaces of the bearing journal 152, crankpin 154, and / or crank web 156. The addition of this filler material 162 helps further attenuate vibration, bending, and torsional forces experienced by the crankshaft assembly 111. Conversely, the cavity space between the reinforcing rod 160 and the ID surface of the crankshaft body 150 may be left empty, for example, to serve as a fluid conduit for lubricant delivery. An optional steel block (not shown) may be cast into or otherwise mounted to the counterweight 158 ​​to counteract the inertia of the internal reinforcing structure 160. Additionally, the interface surfaces of the internal reinforcement structure 160 in contact with the ID surfaces of the journal, crankpin, and web cavities 151 , 153 , 155 may be textured to increase the mechanical adhesion between the reinforcement rod 160 and the crankshaft body 150 .

[0084] Next go to Figure 3 , shows another representative engine crankshaft assembly 211, which is generally composed of a crankshaft body 250 having a plurality of discrete encapsulated reinforcement structures 260 (also referred to herein as "I-beam core reinforcements") encapsulated within selected sections of the crankshaft body 250. As mentioned above, the crankshaft assembly 211 can be configured as described above with respect to Figure 1 Crankshaft 11 or Figure 2For example, the crankshaft body 250 includes a plurality of main bearing journals 252, a plurality of crank pins 254 interleaved with the bearing journals 252, a plurality of crank webs 256 that physically connect the bearing journals 252 to the crank pins 254, and an optional counterweight 258 connected to one or more of the crank webs 256.

[0085] Rather than using a single-piece internal reinforcement structure extending through multiple areas of the crankshaft (e.g. Figure 2 and 4 those shown in ), Figure 3 The crankshaft assembly 211 employs a set of discrete, packaged I-beam reinforcement rods 260, each mounted within a corresponding location within the crankshaft body 250. As shown, the I-beam reinforcement rods 260 are rigidly mounted within discrete crankpin cavities 253 within the crankpins 254 and extend through adjacent web cavities 255 of the crank web 256 adjacent to the corresponding crankpins 254. In this example, the web cavities 255 are through-holes having a pair of axially spaced openings, one of which is adjacent to the crankpin cavities 253 and the other of which is unobstructed and opens to the exterior of the crankshaft body 250. With this configuration, the discrete, packaged reinforcement rods 260 protrude from the unobstructed, open ends of the web cavities 255 in the crank web 256 adjacent to the crankpins 254, with the reinforcement rods 260 permanently attached thereto. The exposed ends of the I-beam stiffeners 260 may be trimmed or machined away during standard crankshaft machining, for example, to save on assembly and manufacturing costs. Figure 3 The reinforcing rod 260 is shown extending diametrically across and coextensive with the cavities 253 , 255 .

[0086] Figure 4 Another representative engine crankshaft assembly 311 is depicted, comprising a crankshaft body 350 having an internally encapsulated reinforcement structure 360 ​​(also referred to herein as a "torsional I-beam reinforcement") extending longitudinally through some, but not all, of the crankshaft body 350. Figure 2 and Figure 3 The crankshaft assemblies 111 and 211, Figure 4 The crankshaft body 350 includes longitudinally spaced main bearing journals 352 interconnected with axially offset crank pins 354 via staggered crank webs 356. An optional set of radially projecting, circumferentially spaced counterweights 358 are shown connected to the crank webs 356.

[0087] The torsional I-beam reinforcement 360 has an elongated, nonlinear beam body that extends through the selected journal cavity, the selected crankpin cavity, and the selected web cavity; however, the torsional I-beam reinforcement 360 is completely located within the crankshaft body 350 and therefore does not protrude from the opposite longitudinal ends of the crankshaft body 350. In order to pass through the internal cavity network of the crankshaft body 350, the body of the torsional I-beam reinforcement 360 is bent transversely relative to the central axis of the I-beam reinforcement 360 (e.g., at Figure 3 vertically upward and downward in the Figure 4 (Twist clockwise in the middle). In the illustrated example, the twisted I-beam reinforcement rod 360 does not extend diametrically across the journal / crankpin / web cavities, but instead has an I-beam height that is less than the inner diameter of these cavities. The I-beam can have a variable height and width along its length, with a smaller height in the crank arm 356. The I-beam can also be contained in a sand core near its ends. The last 10-30 mm of the beam can be encased in sand, eliminating the need for machining the steel beam.

[0088] Some optional configurations can be combined Figure 3 and 4 The invention relates to a method for manufacturing a crankshaft having a plurality of internal reinforcing structures, wherein the internal reinforcing structure is a single piece extending through the cavity of the crankshaft body; (2) sections of the internal reinforcing structure within the main and rod bearing journals extend diametrically across and coextensive with their internal cavities; and (3) sections of the internal reinforcing structure within the crank web are twisted and have a reduced height to accommodate the transition cavity within the web. A preferred embodiment may consist of a steel I-beam with each end enclosed in a sand core, for example the last approximately 20 mm. An additional approximately 20 mm to approximately 50 mm of the core print may extend beyond the crankshaft body to secure the internal I-beam during the crankshaft casting process. After the casting cools, the sand is removed from the core (e.g., shaken out) leaving the I-beam recessed 20 mm within the casting.

[0089] Various aspects of the present disclosure have been described in detail with reference to the illustrated embodiments; however, those skilled in the art will recognize that many modifications may be made thereto without departing from the scope of the present disclosure. The present disclosure is not limited to the precise construction and compositions disclosed herein; any and all modifications, changes, and variations apparent from the foregoing description are within the scope of the present disclosure as defined by the appended claims. Furthermore, the present concept expressly encompasses any and all combinations and subcombinations of the aforementioned elements and features.

Claims

1. A crankshaft assembly comprising: A crankshaft body formed of a first material and comprising: a plurality of bearing journals coaxial with one another for rotation on the crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therein; a plurality of crankpins spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis, each crankpin defining a crankpin cavity therein; and a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journal and the crank pin, each crank web defining a web cavity therein; and a reinforcing rod disposed within one or more of the journal cavity, the crankpin cavity, and / or the web cavity, the reinforcing rod being formed of a second material having a second elastic modulus greater than a first elastic modulus of the first material; Wherein, the journal cavity of the bearing journal and the crankpin cavity of the crankpin are connected through the web cavity, and the web cavity extends through the crank web.

2. The crankshaft assembly according to claim 1, wherein: The reinforcement bar includes an I-beam reinforcement having an I-shaped cross-section with a stem connecting the legs and arms.

3. The crankshaft assembly according to claim 2, wherein: Each of the legs and arms includes a pair of corresponding opposing lateral ends having rounded edges.

4. The crankshaft assembly according to claim 2, wherein: The I-shaped cross-section also includes a first circular protrusion projecting radially from the outer diameter (OD) surface of the leg and a second circular protrusion projecting radially from the OD surface of the arm.

5. The crankshaft assembly according to claim 2, wherein: The arms and legs have a first thickness, and the stem has a second thickness that is less than the first thickness.

6. The crankshaft assembly of claim 1 further comprising a filler material disposed in the journal cavity, crankpin cavity and / or web cavity and interposed between the reinforcing rod and the bearing journal, crankpin and / or crank web.

7. The crankshaft assembly according to claim 1, wherein: The reinforcement rod includes an interface surface where it contacts an inner diameter (ID) surface of the journal cavity, crankpin cavity, and / or web cavity, the interface surface having a surface texture configured to increase mechanical adhesion between the reinforcement rod and the crankshaft body.

8. The crankshaft assembly of claim 1, wherein: The reinforcement bar includes an I-beam reinforcement having an elongated nonlinear beam body extending through the journal cavity, the crankpin cavity, and the web cavity.

9. The crankshaft assembly according to claim 8, wherein: The beam body of the I-beam reinforcement bends laterally and rotates circumferentially relative to the central axis of the I-beam reinforcement.

10. The crankshaft assembly of claim 1, wherein: The reinforcement rod includes a plurality of discrete reinforcement rods, each reinforcement rod being mounted within a respective one of the journal cavity, the crankpin cavity, and / or the web cavity.

11. The crankshaft assembly according to claim 10, wherein: Each of the journal cavity, crankpin cavity, and web cavity includes a through-hole with a hollow core having opposing open ends, and wherein each discrete reinforcement rod is located within a corresponding one of the hollow cores and protrudes from the open end of the hollow core.

12. The crankshaft assembly of claim 1, wherein: The first material comprises aluminum, an aluminum alloy, or ductile iron, and wherein the second material comprises steel, a steel alloy, or ceramic.

13. The crankshaft assembly of claim 1, wherein: The crankshaft body, including the bearing journal, crank pin and crank web, is integrally formed as a single-piece structure.

14. A motor vehicle comprising: vehicle body; a plurality of wheels rotatably attached to the vehicle body; and An internal combustion engine (ICE) assembly attached to a vehicle body and operable to output engine torque to one or more of the wheels, thereby propelling the motor vehicle, the ICE assembly having an engine block defining a plurality of cylinder bores, a plurality of pistons each reciprocally movable within a respective one of the cylinder bores, and a crankshaft assembly, the crankshaft assembly comprising: A single-piece crankshaft body formed of a first material and comprising: a plurality of bearing journals rotatably attached to the engine block, coaxial with one another for rotation on the crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therethrough; a plurality of crankpins, each coupled to a respective one of the pistons, spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis for orbital rotation about the crankshaft axis, each crankpin defining a crankpin cavity therethrough; and a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journal and the crank pin, each crank web defining a web cavity therethrough; and An I-beam reinforcement having an elongated nonlinear beam body that bends laterally and rotates circumferentially relative to a central axis of the I-beam reinforcement, the I-beam reinforcement extending through the journal cavity, the crankpin cavity, and the web cavity, the I-beam reinforcement being formed of a second material having a second elastic modulus greater than a first elastic modulus of the first material; Wherein, the journal cavity of the bearing journal and the crankpin cavity of the crankpin are connected through the web cavity, and the web cavity extends through the crank web.

15. A method of manufacturing a crankshaft assembly, the method comprising: A crankshaft body is formed from a first material, the crankshaft body comprising: a plurality of bearing journals coaxial with one another for rotation on the crankshaft axis and spaced apart from one another along the length of the crankshaft body, each bearing journal defining a journal cavity therein; a plurality of crankpins spaced apart from one another along the length of the crankshaft body and axially offset from the crankshaft axis, each crankpin defining a crankpin cavity therein; and a plurality of crank webs projecting radially from the crankshaft axis and interconnecting the bearing journal and the crank pin, each crank web defining a web cavity therein; and positioning a reinforcing rod within one or more of the journal cavity, the crankpin cavity, and / or the web cavity, the reinforcing rod being formed of a second material having a second elastic modulus greater than a first elastic modulus of the first material; Wherein, the journal cavity of the bearing journal and the crankpin cavity of the crankpin are connected through the web cavity, and the web cavity extends through the crank web.

16. The method of claim 15, wherein the reinforcement bar comprises an I-beam reinforcement having an I-shaped cross-section with a stem connecting the legs and the arms.

17. The method according to claim 16, wherein Each of the legs and arms includes a pair of corresponding opposing lateral ends having rounded edges.

18. The method according to claim 16, wherein The I-shaped cross-section also includes a first circular protrusion projecting radially from the outer diameter (OD) surface of the leg and a second circular protrusion projecting radially from the OD surface of the arm.

19. The method according to claim 15, further comprising: Filler material is added to the journal cavity, crankpin cavity, and / or web cavity and positioned between the reinforcing rod and the bearing journal, crankpin, and / or crank web.

20. The method according to claim 15, wherein The reinforcement bar includes an I-beam reinforcement having an elongated nonlinear beam body extending through the journal cavity, the crankpin cavity, and the web cavity, wherein the beam body bends laterally and rotates circumferentially relative to the crankshaft axis.

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