Hybrid vehicle

Abstract

The present disclosure provides a "hybrid vehicle". A vehicle includes a planetary gear set, a gearbox, an electric motor, and an engine. The planetary gear set has a sun gear, a planet carrier, and a ring gear. The gearbox is configured to transfer power from the ring gear to the wheels. The electric motor is fixedly coupled to the sun gear. The engine is selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch.

Description

Technical Field

[0001] The present disclosure relates to hybrid vehicles and hybrid vehicle powertrain configurations. Background Art

[0002] Hybrid vehicles can utilize multiple power sources to generate power within the powertrain of the hybrid vehicle. Summary of the Invention

[0003] A vehicle includes a planetary gear set, a gearbox, an electric motor, and an engine. The planetary gear set has a sun gear, a planet carrier, and a ring gear. The gearbox is configured to transfer power from the ring gear to the wheels. The electric motor is fixedly coupled to the sun gear. The engine is selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch.

[0004] A vehicle includes a planetary gear set, an electric motor, an engine, and at least one drive wheel. The planetary gear set has a sun gear, a planet carrier, and a ring gear. The electric motor has a rotor fixedly coupled to the sun gear. The engine is selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch. The at least one drive wheel is coupled to the ring gear.

[0005] A vehicle includes a planetary gear set, a multi-ratio transmission, an electric motor, and an engine. The planetary gear set has a sun gear, a planet carrier, and a ring gear. The input of the multi-ratio transmission is fixedly coupled to the ring gear. The electric motor is fixedly coupled to the sun gear. The engine is selectively coupled to the ring gear through a first clutch and selectively coupled to the planet carrier through a second clutch. Brief Description of the Drawings

[0006] Figure 1 is a schematic diagram of an exemplary powertrain of a hybrid electric vehicle;

[0007] Figure 2 is a cross-sectional view of a module including an electric motor and a planetary gear set;

[0008] Figure 3 is a schematic diagram of an exemplary electromagnetic one-way clutch; and

[0009] Figure 4 is a detailed view of the exemplary electromagnetic one-way clutch. Detailed Description

[0010] Embodiments of the present disclosure are described herein. However, it is to be understood that the disclosed embodiments are merely examples and other embodiments may take various forms and alternative forms. The figures are not necessarily drawn to scale; some features may be exaggerated or minimized to show details of particular components. Accordingly, the specific structural and functional details disclosed herein are not to be construed as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ these embodiments. As will be understood by one of ordinary skill in the art, the various features shown and described with reference to any one figure may be combined with features shown in one or more other figures to produce embodiments that are not explicitly shown or described. Combinations of the shown features provide representative embodiments for typical applications. However, for a particular application or implementation, various combinations and modifications of these features may be required in accordance with the teachings of the present disclosure.

[0011] Reference Figure 1 , a schematic view of a hybrid electric vehicle (HEV) 10 according to an embodiment of the present disclosure is shown. Figure 1 Illustrates representative relationships between components. The physical layout and orientation of vehicle interior components may vary. HEV 10 includes a powertrain 12. Powertrain 12 includes an engine 14 that drives a transmission 16. As will be described in further detail below, transmission 16 includes an electric machine (e.g., a motor / generator (M / G) 18), a gearbox 24, and a planetary gear set 26.

[0012] A transmission, such as gearbox 24 and / or planetary gear set 26, is a collection of rotating elements and / or clutches configured to impose a specified speed relationship between the elements. Some speed relationships, called fixed speed relationships, are independent of the state of any clutch. A transmission that only imposes a fixed relationship is called a fixed transmission. Other speed relationships are only imposed when a particular clutch is fully engaged. A transmission that selectively imposes a speed relationship is called a shiftable transmission. A discrete ratio transmission has a shiftable transmission that selectively imposes various ratios between an input shaft and an output shaft.

[0013] If a set of components is constrained to rotate as a unit under all operating conditions, they are fixedly coupled to each other. The components can be fixedly coupled by spline connection, welding, press fitting, machining from the same solid, or other means. There may be slight variations in the rotational displacement between the fixedly coupled components, such as those caused by clearances or shaft flexibility. In contrast, when a clutch restricts two components from rotating as a unit as long as the clutch is fully engaged, the two components are selectively coupled by the clutch and they rotate freely at different speeds under at least some other operating conditions. The clutch includes an active control device (such as a hydraulic or electric clutch) and a passive device (such as a one-way clutch). A clutch that holds a component from rotating by selectively connecting it to a fixed member (such as a transmission housing) can be referred to as a brake.

[0014] The planetary gear set 26 can include a sun gear 25, a planet carrier 27, and a ring gear 29. The planet carrier 27 can be fixedly coupled to the sun gear 25 and the ring gear 29 by one or more planet gears (not shown). The engine 14 (or more specifically, the crankshaft 28 of the engine 14) can be selectively coupled to the ring gear 29 by a first optional one-way clutch 31. When the first optional one-way clutch 31 is disengaged, the engine 14 and the ring gear 29 can be separated. When the first optional one-way clutch 31 is engaged, the engine 14 and the ring gear 29 can be connected. When the first optional one-way clutch 31 is engaged, the engine 14 can drive the planetary gear set 26 (or more specifically, the ring gear 29) and deliver power to it in the rotational operating direction of the engine 14 (whether clockwise or counterclockwise).

[0015] The engine 14 (or more specifically, the crankshaft 28) can also be selectively coupled to the planet carrier 27 by a second optional one-way clutch 33. When the second optional one-way clutch 33 is disengaged, the engine 14 and the planet carrier 27 can be separated. When the second optional one-way clutch 33 is engaged, the engine 14 and the planet carrier 27 can be connected. When the second optional one-way clutch 33 is engaged, the engine 14 can drive the planetary gear set 26 (or more specifically, the planet carrier 27) and deliver power to it in the rotational operating direction of the engine 14.

[0016] A third one-way clutch 35, which can be a non-optional one-way clutch, prevents the planet carrier from rotating in a direction opposite or contrary to the rotational operating direction of the engine 14. A fourth one-way clutch 37, which can be an optional one-way clutch, can selectively couple the engine 14 (or more specifically, the crankshaft 28) and the planet carrier 27 in a direction opposite to the rotational operating direction of the engine 14. The second optional one-way clutch 33 and the fourth optional one-way clutch 37 can be a single clutch that includes two sets of rockers that engage in opposite directions. The following Figure 3 and Figure 4An example of an optional one-way clutch is shown, which has rockers that engage in a single direction. An improved clutch includes a first set of rockers that engage notches in a clockwise direction (as shown in the clutch of Figure 3 and Figure 4 ) and a set of rockers that engage notches in a counterclockwise direction (not shown in the clutches of Figure 3 and Figure 4 ). Such a clutch can be used as a single clutch that includes a second optional one-way clutch 33 and a fourth optional one-way clutch 37. It should be understood that the engagement of the fourth one-way clutch 37 does not cause the carrier 27 or the engine 14 to rotate in a direction opposite to the rotational operating direction of the engine 14, but only allows torque or power to flow from the carrier 27 to the engine 14, which may occur in certain situations. For example, when the HEV 10 decelerates during throttle release or when brakes are applied to decelerate the HEV 10, torque or power can flow from the carrier 27 to the engine 14.

[0017] Both the engine 14 and the M / G 18 are drive sources of the HEV 10. The engine 14 generally represents a power source, which may include an internal combustion engine (e.g., a gasoline-, diesel-, or natural gas-powered engine) or a fuel cell. The engine 14 generates engine power and corresponding engine torque, which is provided to the planetary gear set 26 (or more specifically, the ring gear 29 or the carrier 27) according to the states of the one-way clutches 31, 33. The M / G 18 can be implemented by any of a variety of types of electric motors. For example, the M / G 18 can be a permanent magnet synchronous motor. The power electronics device regulates the direct current (DC) power provided by the power battery 20 to the requirements of the M / G 18, as described below. For example, the power electronics device can provide three-phase alternating current (AC) to the M / G 18. The M / G 18 is fixedly coupled to the sun gear 25 of the planetary gear set 26. More specifically, the rotor of the M / G 18 is fixedly coupled to the sun gear 25.

[0018] The M / G 18 can operate as a motor and generate power and corresponding torque, which is provided to the planetary gear set 26 (or more specifically, the sun gear 25). Alternatively, power and corresponding torque can be transferred from the planetary gear set 26 to the M / G 18, such that the M / G 18 can charge the battery 20 as a generator. More specifically, power can be transferred from the engine 14 or through regenerative braking via the planetary gear set 26 to the M / G 18, such that the M / G 18 can charge the battery 20 as a generator. When the M / G 18 delivers power to the planetary gear set 26, the M / G 18 (or the rotor of the M / G 18) and the sun gear 25 rotate in a direction opposite to or contrary to the rotational operating direction of the engine 14. When power is transferred from the planetary gear set 26 to the M / G 18, the M / G 18 and the sun gear 25 rotate in the operating direction of the engine 14.

[0019] The M / G 18 can also adjust the rotational speed of the ring gear 29 in a manner similar to a continuously variable transmission, while the engine 14 delivers power to the planetary gear set 26 through the planet carrier 27 or the ring gear 29. Adjusting the rotational speed of the ring gear using the M / G 18 while the engine 14 delivers power to the planetary gear set 26 can be referred to as an electronically controlled continuously variable transmission (ECVT) mode.

[0020] The gearbox 24 can include only fixedly coupled rotating elements (e.g., shafts or gears) configured to provide a single gear ratio between the input shaft 32 and the output shaft 36 of the gearbox 24. Alternatively, the gearbox 24 can be a multi-speed automatic transmission that includes fixedly coupled rotating elements (e.g., shafts or gears) and selectively coupled rotating elements (e.g., clutches) configured to provide multiple gear ratios between the input shaft 32 and the output shaft 36 of the gearbox 24. More specifically, the gearbox 24 can include a gear set (not shown) that is selectively placed in different gear ratios by selectively engaging friction elements such as clutches and brakes (not shown) to establish a desired plurality of discrete or stepped gear ratios. The friction elements can be controlled by a shift schedule that connects and disconnects certain elements of the gear set to control the gear ratio between the transmission output shaft 36 and the transmission input shaft 32. Based on various vehicle and environmental operating conditions, the gearbox 24 automatically switches from one gear ratio to another via an associated controller (e.g., a powertrain control unit (PCU)). Power and torque from the engine 14 and the M / G 18 can be transmitted to and received by the gearbox 24 via the planetary gear set 26 (or more specifically, the ring gear 29 that is fixedly coupled to the input shaft 32 of the gearbox 24). The gearbox 24 then provides the powertrain output power and torque to the output shaft 36 and ultimately to the drive wheels 42 of the HEV 10.

[0021] It should be understood that the hydraulically controlled gearbox 24 is merely an example of a gearbox or transmission. Any single- or multi-speed gearbox that receives input torque from an engine and / or a motor and then provides torque to an output shaft can be used in embodiments of the present disclosure. For example, the gearbox 24 can be implemented by an automated mechanical (or manual) transmission (AMT) that includes one or more servo motors to translate / rotate a shift fork along a shift rail to select a desired gear ratio. As is commonly understood by those of ordinary skill in the art, AMTs can be used, for example, in applications with higher torque requirements.

[0022] As Figure 1As shown in the representative embodiment, the output shaft 36 is connected to the differential 40. The differential 40 is in turn connected to the drive wheels 42 via respective axles 44 connected to the differential 40. The differential transmits substantially equal torque to each wheel 42 while allowing for a slight difference in rotational speed, such as when the vehicle is turning. Different types of differentials or similar devices can be used to distribute torque from the powertrain to one or more wheels. In some applications, the torque distribution can vary depending on, for example, specific operating modes or conditions.

[0023] The gearbox 24 (or more specifically, the output shaft 36) can be fixedly coupled to the drive wheels 42 via the differential 40 and the axles 44. Alternatively, if a clutch is provided somewhere between the gearbox 24 and the drive wheels 42, the gearbox 24 can be selectively coupled to the drive wheels 42 via the differential 40 and the axles 44. For example, the differential can be a sliding differential that includes one or more clutches. In the case where the gearbox includes only one gear ratio and no other clutches are provided between the ring gear 29 and the drive wheels 42, the ring gear 29 can be fixedly coupled to the drive wheels 42 via the input shaft 32, the gearbox 24, the output shaft 36, the differential 40, and the axles 44. Alternatively, if a clutch is provided somewhere between the ring gear 29 and the drive wheels 42, the ring gear 29 can be selectively coupled to the drive wheels 42 via the input shaft 32, the gearbox 24, the output shaft 36, the differential 40, and the axles 44. For example, the gearbox 24 can be a multi-stage automatic transmission that includes one or more clutches.

[0024] The powertrain 12 also includes an associated controller 50, such as a powertrain control unit (PCU). Although shown as a single controller, controller 50 can be part of a larger control system and can be controlled by various other controllers (such as a vehicle system controller (VSC)) throughout vehicle 10. It should thus be understood that the powertrain control unit 50 and one or more other controllers can be collectively referred to as "controllers" that control various actuators in response to signals from various sensors to control functions such as starting / stopping engine 14, operating M / G 18 to provide wheel torque or charge battery 20, and selecting or scheduling transmission shifts. Controller 50 can include a microprocessor or central processing unit (CPU) that communicates with various types of computer-readable storage devices or media. The computer-readable storage devices or media can include, for example, volatile and non-volatile memories such as read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM). KAM is a persistent or non-volatile memory that can be used to store various operating variables when the CPU is powered down. The computer-readable storage devices or media can be implemented using any of a number of known memory devices, such as PROM (programmable read-only memory), EPROM (electrical PROM), EEPROM (electrically erasable PROM), flash memory, or any other electrical, magnetic, optical, or combination memory device capable of storing data, some of which provide executable instructions used by the controller to control the engine or vehicle.

[0025] The controller communicates with various engine / vehicle sensors and actuators via an input / output (I / O) interface (including input and output channels), which can be implemented as a single integrated interface that provides various raw data or signal conditioning, processing, and / or conversion, short-circuit protection, etc. Alternatively, one or more dedicated hardware or firmware chips can be used to condition and process specific signals before being provided to the CPU. As Figure 1As shown generally in the representative embodiment, controller 50 can communicate signals with engine 14, M / G 18, battery 20, transmission gearbox 24, first optional one-way clutch 31, second optional one-way clutch 33, fourth one-way clutch 37, and power electronics 56. Although not explicitly stated, those of ordinary skill in the art will recognize the various functions or components within each of the above subsystems that can be controlled by controller 50. Representative examples of parameters, systems, and / or components that can be actuated directly or indirectly using control logic and / or algorithms executed by the controller include: fuel injection timing, rate, and duration, throttle position, spark plug ignition timing (for spark ignition engines), intake / exhaust valve timing and duration, front end accessory drive (FEAD) components (such as alternators, air conditioning compressors), battery charging or discharging (including determining maximum charge / discharge power limits), regenerative braking, M / G operation, clutch pressure of transmission gearbox 24, etc. Sensors that transmit inputs through the I / O interface can be used to indicate, for example, turbocharger boost pressure, crankshaft position (PIP), engine speed (RPM), wheel speed (WS1, WS2), vehicle speed (VSS), coolant temperature (ECT), intake manifold pressure (MAP), accelerator pedal position (PPS), ignition switch position (IGN), throttle position (TP), air temperature (TMP), exhaust oxygen (EGO) or other exhaust component concentration or presence, intake air flow (MAF), transmission gear, gear ratio or mode, transmission oil temperature (TOT), deceleration or shift mode (MDE), battery temperature, voltage, current, or state of charge (SOC).

[0026] The control logic or functions executed by the controller 50 may be represented by flowcharts or similar diagrams in one or more of the figures. These diagrams provide representative control strategies and / or logic, which may be implemented using one or more processing strategies such as event-driven, interrupt-driven, multitasking, multithreading, etc. Accordingly, the various steps or functions shown may be executed in the order shown, executed in parallel, or in some cases may be omitted. Although not always explicitly shown, one of ordinary skill in the art will recognize that one or more of the steps or functions shown may be executed repeatedly depending on the particular processing strategy used. Similarly, the order of processing is not necessarily required to implement the features and advantages described herein, but is provided for ease of illustration and description. The control logic may be implemented primarily in software executed by a microprocessor-based vehicle, engine, and / or powertrain controller such as controller 50. Of course, depending on the particular application, the control logic may be implemented in one or more controllers in software, hardware, or a combination of software and hardware. When implemented in software, the control logic may be provided on one or more computer-readable storage devices or media that store data providing code or instructions for execution by a computer to control the vehicle or its subsystems. The computer-readable storage device or medium may include one or more of many known physical devices that utilize electrical, magnetic, and / or optical memory to store executable instructions and associated calibration information, operating variables, etc.

[0027] The vehicle driver uses the accelerator pedal 52 to provide the required torque, power, or drive command to propel the vehicle. Typically, depressing and releasing the accelerator pedal 52 generates an accelerator pedal position signal that may be interpreted by the controller 50 as a need to increase or decrease power, respectively. The vehicle driver also uses the brake pedal 58 to provide the required braking torque to decelerate the vehicle. Typically, depressing and releasing the brake pedal 58 generates a brake pedal position signal that may be interpreted by the controller 50 as a request to reduce vehicle speed. Based on inputs from the accelerator pedal 52 and the brake pedal 58, the controller 50 commands the torque delivered to the engine 14, M / G 18, and friction brake 60. If the gearbox 24 is a multi-stage automatic transmission, the controller 50 also controls the shift timing within the gearbox 24.

[0028] To drive the vehicle with the engine 14, the first optional one-way clutch 31 or the second optional one-way clutch 33 will be engaged to transfer power and torque from the engine 14 to the gearbox 24 through the planetary gear set 26. The M / G 18 may provide additional power to the gearbox 24 through the planetary gear set 26 to assist the engine 14. This operating mode may be referred to as a "hybrid mode" or an "electric assist mode".

[0029] To drive the vehicle with the M / G 18 as the sole power source, the first optional one-way clutch 31 and the second optional one-way clutch 33 will disengage to isolate the engine 14 from the planetary gear set 26 and the rest of the powertrain 12, while the third one-way clutch 35 keeps the carrier 27 stationary. During this period, combustion in the engine 14 can be disabled or otherwise shut down to save fuel. The power battery 20 transmits the stored electrical energy to the power electronics 56 through the wiring 54, and the power electronics may include, for example, an inverter. The power electronics 56 converts the DC voltage from the battery 20 into an AC voltage to be used by the M / G 18. The controller 50 commands the power electronics 56 to convert the voltage from the battery 20 into an AC voltage to be supplied to the M / G 18 to provide positive or negative torque to the sun gear 25 of the planetary gear set 26. This operating mode can be referred to as the "pure electric" or "EV" operating mode.

[0030] In any operating mode, the M / G 18 can be used as a motor and provide driving force for the powertrain 12. Alternatively, the M / G 18 can be used as a generator and convert the kinetic energy from the powertrain 12 into electrical energy to be stored in the battery 20. For example, when the engine 14 provides propulsion power for the vehicle 10, the M / G 18 can be used as a generator. The M / G 18 can also act as a generator during regenerative braking, where the torque and rotational (or power) energy or power from the rotating wheels 42 are transmitted back through the gearbox 24 and the planetary gear set 26 and converted into electrical energy to be stored in the battery 20.

[0031] In response to conditions or commands for the HEV 10 to operate in a specific operating mode, the controller 50 can be programmed to operate the engine 14 and / or the M / G 18 based on the specific operating mode. Moreover, in response to conditions or commands for the HEV 10 to operate in a specific operating mode, the controller 50 can be programmed to engage or disengage the first optional one-way clutch 31, the second optional one-way clutch 33, and / or the fourth one-way clutch 37.

[0032] In the pure electric drive mode, only the M / G 18 is commanded to operate to deliver power and / or torque to the planetary gear set 26, and the controller 50 is programmed to disengage the first optional one-way clutch 31, disengage the second optional one-way clutch 33, and keep the carrier 27 from rotating (which can be achieved by the third one-way clutch 35). More specifically, in the pure electric drive mode, the power and / or torque of the M / G 18 is transmitted to the ring gear 29 of the planetary gear set 26 via the M / G 18 that rotates the sun gear 25. Then, the ring gear 29 transmits the power and / or torque of the M / G 18 to the rest of the powertrain 12.

[0033] In a mode where the engine 14 is commanded to supply power to the M / G 18 (i.e., supply power to the M / G 18 to operate the M / G 18 as a generator) to charge the battery 20 when the HEV 10 is stopped, the controller 50 is programmed to disengage the first selectable one-way clutch 31, engage the second selectable one-way clutch 33, and brake the ring gear 29 to prevent the ring gear 29 from rotating. More specifically, when switching to the charging mode when the HEV 10 is stopped, the operation sequence may include starting the engine 14, increasing the rotational speed of the M / G 18 to a rotational speed greater than the rotational speed of the crankshaft 28, deploying the second selectable one-way clutch 33, and slowing down the rotational speed of the M / G 18 to engage the second selectable one-way clutch 33. The selectable one-way clutch can be deployed without being affected by the environment, for example when the clutch is in an overrunning state. For example, the one-way clutch may include a rocker provided on a first side of the clutch, and when the rocker is deployed, the rocker engages a notch on the opposite side of the clutch (see Figure 3 and 4 ). If the opposite side of the clutch rotates faster than the first side of the clutch, the rocker may be deployed but not engaged. Once the second selectable one-way clutch 33 is engaged, the rotational speeds of the crankshaft 28 and the rotor of the M / G 18 will be synchronized, and the engine 14 can then be operated to rotate the rotor of the M / G 18 to generate electricity, thereby charging the battery 20. The ring gear 29 and the remainder of the power transmission system 12 from the drive wheels 42 to the ring gear 29 can be kept stationary during the charging mode by a braking mechanism such as a friction brake 60 located at the drive wheels 42. An alternative mode in which the engine 14 is commanded to supply power to the M / G 18 may include programming the controller 50 to engage the first selectable one-way clutch 31 and disengage the second selectable one-way clutch 33.

[0034] In the first hybrid mode, both the engine 14 and the M / G 18 are commanded to deliver power to the planetary gear set 26. The controller 50 is programmed to engage the first optional one-way clutch 31, disengage the second optional one-way clutch 33, and brake the planet carrier 27 to keep the planet carrier 27 from rotating (which can be achieved by the third one-way clutch 35). The first hybrid mode can also be an ECVT mode, in which the M / G 18 regulates the rotational speed of the ring gear while the engine 14 also delivers power to the planetary gear set 26. More specifically, when transitioning to the first hybrid mode, the operation sequence can include starting the engine 14 and deploying the first optional one-way clutch 31. Once the rotational speed of the engine 14 reaches the rotational speed of the ring gear 29, the first optional one-way clutch 31 will engage, and then the engine 14 will directly supply power and torque to the ring gear 29. In the first hybrid mode, the power and torque of the M / G 18 are transmitted to the ring gear 29 of the planetary gear set 26 by rotating the sun gear 25 with the M / G 18. Then, the ring gear 29 transmits the power and torque of the engine 14 and the M / G 18 to the rest of the powertrain 12. The first hybrid drive mode can be used during engine start-up while the vehicle is in motion, during wide open throttle (WOT) conditions, in which maximum torque is commanded to the ring gear 29, or any other suitable condition.

[0035] In the second hybrid mode, both the engine 14 and the M / G 18 are commanded to deliver power to the planetary gear set 26. The controller 50 is programmed to disengage the first optional one-way clutch 31 and engage the second optional one-way clutch 33. The second hybrid mode can also be an ECVT mode, in which the M / G 18 regulates the rotational speed of the ring gear while the engine 14 also delivers power to the planetary gear set 26. More specifically, when transitioning to the second hybrid mode, the operation sequence can include starting the engine 14 and deploying the second optional one-way clutch 33. Once the rotational speed of the engine 14 reaches the rotational speed of the planet carrier 27, the second optional one-way clutch 33 will engage, and then the engine 14 will directly supply power and torque to the planet carrier 27. Alternatively, the HEV 10 can transition from a charging mode (in which the engine 14 is already running and the second optional one-way clutch 33 is already engaged) to the second hybrid mode by causing the M / G 18 to switch from operating as a generator (where the rotor of the M / G 18 and the sun gear 25 rotate in the same direction as the operation direction of the engine 14) to operating as a motor (where the rotor of the M / G 18 and the sun gear 25 rotate in the direction opposite to the rotational operation direction of the engine 14).

[0036] In the pure engine drive mode (or direct drive mode), only the engine 14 is commanded to operate to deliver power and torque to the planetary gear set 26, and the controller 50 is programmed to engage the first optional one-way clutch 31 and disengage the second optional one-way clutch 33. More specifically, when transitioning to the pure engine drive mode, the sequence of operations may include starting the engine 14 and deploying the first optional one-way clutch 31. Once the rotational speed of the engine 14 reaches the rotational speed of the ring gear 29, the first optional one-way clutch 31 will engage, and then the engine 14 will directly supply power and torque to the ring gear 29. During the pure engine drive mode, the M / G 18 may be commanded to shut down (i.e., not operate as a generator or motor).

[0037] The controller 50 may be programmed to implement a series of steps when transitioning the HEV 10 from the pure engine drive mode to the second hybrid mode. First, the M / G 18 is commanded to rotate the sun gear 25 in the same direction as the rotational direction of the ring gear 29 (which is also the operating direction of the engine 14) until the rotational speed of the planet carrier 27 (which also rotates in the operating direction of the engine 14) becomes greater than the rotational speed of the engine 14 (i.e., the rotational speed of the crankshaft 28). Once the rotational speed of the planet carrier 27 becomes greater than the rotational speed of the engine 14, the second optional one-way clutch 33 is deployed. Once the second optional one-way clutch 33 is deployed, the rotational speed of the M / G18 is decreased to reduce the rotational speed of the planet carrier 27 such that the second optional one-way clutch 33 engages and transfers engine torque from the ring gear 29 to the planet carrier 27. Once engine torque is transferred from the ring gear 29 to the planet carrier 27, the first optional one-way clutch 31 may be retracted. The first optional one-way clutch 31 may enter an overrunning state before its retraction.

[0038] The controller 50 may be programmed to implement another series of steps when transitioning the HEV 10 from the second hybrid mode to the pure engine drive mode. First, the M / G 18 is commanded to rotate the sun gear 25 in the direction opposite to the rotation of the ring gear 29 (opposite to the rotational operating direction of the engine 14) until the rotational speed of the planet carrier 27 (which rotates in the operating direction of the engine 14) becomes less than the rotational speed of the engine 14 (i.e., the rotational speed of the crankshaft 28) and until the rotational speed of the ring gear 29 (which also rotates in the operating direction of the engine 14) becomes greater than the rotational speed of the engine 14. Once the rotational speed of the ring gear 29 becomes greater than the rotational speed of the engine 14, the first optional one-way clutch 31 is deployed. Once the first optional one-way clutch 31 is deployed, the rotational speed of the M / G 18 is decreased to reduce the rotational speed of the ring gear 29 such that the first optional one-way clutch 31 engages and engine torque is transferred from the planet carrier 27 to the ring gear 29. Once engine torque is transferred from the planet carrier 27 to the ring gear 29, the second optional one-way clutch 33 may be retracted. The second optional one-way clutch 33 may enter an overrunning state before its retraction.

[0039] It should be understood that Figure 1 the schematic diagrams shown are merely exemplary and not restrictive. Other configurations for transmitting power through a transmission using selective engagement of an engine and a motor can be envisioned. For example, an additional motor can be provided to start the engine 14. Other configurations can be expected without departing from the scope of the present disclosure.

[0040] Referring to Figure 2 , a cross-sectional view of module 62 is shown, which includes M / G 18 and a planetary gear set 26 that includes a sun gear 25, a planet carrier 27, and a ring gear 29. Planetary gears 64 are rotatably fixed to the planet carrier 27. The planetary gears 64 fixedly couple the planet carrier 27 to the sun gear 25 and the ring gear 29. Module 62 can be a modular component that is disposed between the engine 14 and the gearbox 24 and includes an outer housing 66. Alternatively, the housing 66 can be a part of the housing that contains various components (i.e., gears, shafts, clutches, etc.) within the gearbox 24. For example, the housing 66 can be the part of the gearbox housing that typically contains the torque converter (i.e., the bell housing). M / G 18 includes a stator 68 fixed to the housing 66 and a rotor 70 fixed to the sun gear 25. Components of a first optional one-way clutch 31 are integrated into the crankshaft 28 (or some intermediate assembly fixed to the crankshaft 28) and the ring gear 29 (or some intermediate assembly fixed to the ring gear 29). Components of a second optional one-way clutch 33 and a fourth one-way clutch 37 are integrated into the crankshaft 28 (or some intermediate assembly fixed to the crankshaft 28) and the planet carrier 27 (or some intermediate assembly fixed to the planet carrier 27). Components of a third one-way clutch 35 are integrated between the planet carrier 27 and the housing 66 such that the planet carrier 27 can rotate in the direction of rotation of the engine 14 and is held from rotating in the direction opposite to the direction of rotation of the engine 14.

[0041] Now referring to Figure 3 and Figure 4, schematically shows a rocker one-way clutch 72 (which can be an electromagnetic clutch) that can be used in combination with the present disclosure. More specifically, a clutch similar to the rocker one-way clutch 72 can be used as the first optional one-way clutch 31, the second optional one-way clutch 33, and / or the fourth one-way clutch 37. The one-way clutch 72 includes a rocker plate 74 having cavities 76, each cavity 76 containing a corresponding rocker 78, and the rocker 78 is pivotally hinged within the corresponding cavity 76. The clutch 72 also includes a cam plate 80 having a plurality of notches 82 that define teeth. When the rocker 78 pivots relative to the cavity 76, the teeth can grip an inwardly extending portion of the rocker 78. The rocker 78 is biased by a spring 84 to remain within the cavity without protruding. In this configuration, there is no engagement between the rocker 78 and the notch 82, and thus no torque is transmitted between the rocker plate 74 and the cam plate 80. Figure 3 The clutch 72 in this disengaged position is shown.

[0042] The cam plate 80 includes a coil (not shown) that can be selectively energized to generate a magnetic force and engage the clutch 72. In response to the magnetic force, the rocker 78 pivots outwardly (i.e., unfolds) from the cavity 76 against the biasing force of the spring 84, such that a portion of the rocker 78 protrudes beyond the radially inward face of the rocker plate 74. The protruding portion of the rocker 78 can engage the notch 82 and transmit torque in one rotational direction between the rocker plate 74 and the cam plate 80. Figure 4 The clutch 72 in this engaged position is shown. Although the rocker plate 74 is shown as the outer race of the clutch 72 and the cam plate 80 is shown as the inner race of the clutch 72, it should be understood that the clutch 72 can include other configurations, such as a configuration where the cam plate 80 is the outer race and the rocker plate 74 is the inner race.

[0043] The terminology used in the specification is descriptive rather than restrictive, and it should be understood that various changes can be made without departing from the spirit and scope of the present disclosure. As previously mentioned, the features of the various embodiments can be combined to form other embodiments that may not be explicitly described or illustrated. Although the various embodiments may have been described as providing advantages with respect to one or more desired characteristics over other embodiments or prior art implementations, one of ordinary skill in the art should recognize that, depending on the specific application and implementation, one or more features or characteristics may be compromised to achieve the desired overall system attributes. Thus, embodiments that are described as having one or more characteristics that are less desirable than other embodiments or prior art implementations are not outside the scope of the present disclosure and may be desirable for a particular application.

[0044] According to the present invention, there is provided a vehicle having: a planetary gear set having a sun gear, a planet carrier, and a ring gear; a gearbox configured to transfer power from the ring gear to a wheel; an electric motor fixedly coupled to the sun gear; and an engine selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch.

[0045] According to one embodiment, the above invention is further characterized by a controller programmed to, in response to a command to operate only the electric motor to deliver power to the ring gear, disengage the first optional one-way clutch, disengage the second optional one-way clutch, and hold the planet carrier stationary.

[0046] According to one embodiment, the above invention is further characterized by a power battery and a controller, wherein the controller is programmed to, in response to a command to operate the engine to provide power to the electric motor to charge the power battery when the vehicle is stopped, disengage the first optional one-way clutch, engage the second optional one-way clutch, and brake the ring gear.

[0047] According to one embodiment, the above invention is further characterized by a controller programmed to, in response to a command to operate the engine and the electric motor in a first hybrid mode, engage the first optional one-way clutch, disengage the second optional one-way clutch, and hold the planet carrier stationary.

[0048] According to one embodiment, the controller is further programmed to, in response to a command to operate the engine and the electric motor in a second hybrid mode, disengage the first optional one-way clutch and engage the second optional one-way clutch.

[0049] According to one embodiment, the above invention is further characterized by a controller programmed to, in response to a command to operate only the engine to deliver power to the ring gear, engage the first optional one-way clutch.

[0050] According to one embodiment, the above invention is further characterized by a power battery and a controller, wherein the controller is programmed to, in response to a command to operate the engine to deliver power to the ring gear and provide power to the electric motor to charge the power battery, engage one of the first and second optional one-way clutches and disengage the other of the first and second optional one-way clutches.

[0051] According to the present invention, there is provided a vehicle having: a planetary gear set having a sun gear, a planet carrier, and a ring gear; an electric motor having a rotor fixedly coupled to the sun gear; an engine selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch; and at least one drive wheel coupled to the ring gear.

[0052] According to one embodiment, the at least one drive wheel is coupled to the ring gear through a multi-ratio transmission.

[0053] According to one embodiment, the above invention is further characterized by a third one-way clutch configured to keep the planet carrier from rotating in the reverse direction.

[0054] According to one embodiment, the above invention is further characterized by a power battery and a controller, wherein the controller is programmed to disengage the first optional one-way clutch, engage the second optional one-way clutch, and brake the ring gear in response to a command to operate the engine to provide power to the electric motor to charge the power battery when the vehicle is stopped.

[0055] According to one embodiment, the above invention is further characterized by a controller programmed to disengage the first optional one-way clutch, disengage the second optional one-way clutch, and keep the planet carrier from rotating in response to a command to operate only the electric motor to deliver power to the ring gear.

[0056] According to one embodiment, the above invention is further characterized by a controller programmed to disengage the first optional one-way clutch and engage the second optional one-way clutch in response to a command to operate the engine and the electric motor in a first hybrid mode.

[0057] According to one embodiment, the controller is further programmed to engage the first optional one-way clutch, disengage the second optional one-way clutch, and keep the planet carrier from rotating in response to a command to operate the engine and the electric motor in a second hybrid mode.

[0058] According to one embodiment, the above invention is further characterized by a controller programmed to engage the first optional one-way clutch in response to a command to operate only the engine to deliver power to the ring gear.

[0059] According to one embodiment, the features of the above invention further lie in a power battery and a controller, wherein the controller is programmed to, in response to a command to operate the engine to deliver power to the ring gear and provide power to the motor to charge the power battery, engage one of the first and second selectable one-way clutches and disengage the other of the first and second selectable one-way clutches.

[0060] According to the present invention, there is provided a vehicle having: a planetary gear set having a sun gear, a planet carrier, and a ring gear; an input of a multi-ratio transmission fixedly coupled to the ring gear; a motor fixedly coupled to the sun gear; and an engine selectively coupled to the ring gear through a first clutch and selectively coupled to the planet carrier through a second clutch.

[0061] According to one embodiment, the first and second clutches are selectable one-way clutches.

[0062] According to one embodiment, the features of the above invention further lie in at least one drive wheel, wherein the output of the multi-ratio transmission is coupled to the at least one drive wheel.

[0063] According to one embodiment, the features of the above invention further lie in a third one-way clutch configured to hold the planet carrier from rotating in the reverse direction.

Claims

1. A vehicle, comprising: a planetary gear set having a sun gear, a planet carrier, and a ring gear; a gearbox configured to transfer power from the ring gear to a wheel; an electric motor fixedly coupled to the sun gear; an engine selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch; and a controller configured to: in response to a command to operate only the electric motor to deliver power to the ring gear, disengage the first optional one-way clutch, disengage the second optional one-way clutch, and hold the planet carrier stationary.

2. The vehicle according to claim 1, further comprising a third one-way clutch configured to prevent the planet carrier from rotating in a direction opposite to the rotational operation direction of the engine.

3. The vehicle according to claim 1, further comprising a power battery, wherein the controller is further configured to: in response to a command to operate the engine to provide power to the electric motor to charge the power battery when the vehicle is stopped, disengage the first optional one-way clutch, engage the second optional one-way clutch, and brake the ring gear.

4. The vehicle according to claim 1, wherein the controller is further configured to: in response to a command to operate the engine and the electric motor in a first hybrid mode, engage the first optional one-way clutch, disengage the second optional one-way clutch, and hold the planet carrier stationary.

5. The vehicle according to claim 4, wherein the controller is further configured to: in response to a command to operate the engine and the electric motor in a second hybrid mode, disengage the first optional one-way clutch and engage the second optional one-way clutch.

6. The vehicle according to claim 1, wherein the controller is further configured to: in response to a command to operate only the engine to deliver power to the ring gear, engage the first optional one-way clutch.

7. The vehicle according to claim 1, further comprising a power battery, wherein the controller is further configured to: in response to a command to operate the engine to deliver power to the ring gear and provide power to the electric motor to charge the power battery, engage one of the first optional one-way clutch and the second optional one-way clutch and disengage the other of the first optional one-way clutch and the second optional one-way clutch.

8. A vehicle, comprising: a planetary gear set having a sun gear, a planet carrier, and a ring gear; an electric motor having a rotor fixedly coupled to the sun gear; an engine selectively coupled to the ring gear through a first optional one-way clutch and selectively coupled to the planet carrier through a second optional one-way clutch; at least one drive wheel coupled to the ring gear; and a controller configured to: in response to a command to operate only the electric motor to deliver power to the ring gear, disengage the first optional one-way clutch, disengage the second optional one-way clutch, and hold the planet carrier stationary.

9. The vehicle according to claim 8, further comprising a third one-way clutch configured to prevent the planet carrier from rotating in a direction opposite to the rotational operation direction of the engine.

10. The vehicle according to claim 8, further comprising a power battery. Wherein, the controller is further configured to: in response to a command to operate the engine to power the motor to charge the power battery when the vehicle is stopped, disengage the first selectable one-way clutch, engage the second selectable one-way clutch, and brake the ring gear.

11. The vehicle according to claim 8, Wherein, the controller is further configured to: in response to a command to operate only the engine to deliver power to the ring gear, engage the first selectable one-way clutch and disengage the second selectable one-way clutch.

12. The vehicle according to claim 8, Wherein, the controller is further configured to: in response to a command to operate the engine and the motor in a first hybrid mode, disengage the first selectable one-way clutch and engage the second selectable one-way clutch.

13. The vehicle according to claim 12, Wherein, the controller is further configured to: in response to a command to operate the engine and the motor in a second hybrid mode, engage the first selectable one-way clutch, disengage the second selectable one-way clutch, and keep the planet carrier from rotating.

14. A vehicle, comprising: a planetary gear set having a sun gear, a planet carrier, and a ring gear; an input of a multi-ratio transmission fixedly coupled to the ring gear; a motor fixedly coupled to the sun gear; an engine selectively coupled to the ring gear through a first clutch and selectively coupled to the planet carrier through a second clutch; and a third clutch configured to prevent the planet carrier from rotating in a direction opposite to the rotational operation direction of the engine.

15. The vehicle according to claim 14, Wherein, the first clutch and the second clutch are selectable one-way clutches.

16. The vehicle according to claim 14, further comprising a controller configured to: in response to a command to operate only the motor to deliver power to the ring gear, disengage the first clutch, disengage the second clutch, and keep the planet carrier from rotating.

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