Multi-mode integrated starter-generator unit with preload clutch

Abstract

A combined starter-generator device includes: an electric machine; a gear set configured to receive rotational input from the electric machine and an engine and to couple the electric machine and the engine in a first power flow direction and a second power flow direction. The gear set is configured to operate in one of a plurality of gear ratios in the first power flow direction and in at least one gear ratio in the second power flow direction. The starter-generator device also includes a clutch device having at least one applied clutch, the at least one applied clutch selectively coupled to the gear set to achieve a gear ratio in the first power flow direction and the second power flow direction. The clutch device also includes at least one drag clutch to apply a drag force to the gear set to decelerate the electric machine.

Description

Technical Field

[0001] The present disclosure relates to a work vehicle power system including an arrangement for starting a mechanical powerplant and generating electrical power therefrom. Background Art

[0002] Work vehicles, such as those used in the agricultural, construction and forestry industries, and other conventional vehicles may be powered by an internal combustion engine (e.g., a diesel engine), although it is becoming increasingly common for hybrid power sources to be employed (e.g., an engine and an electric motor). In any case, the engine remains the primary source of power for the work vehicle, and a mechanical input from a starter is required to initiate the rotation of the crankshaft and the reciprocating motion of the pistons within the cylinders. The torque requirements for starting the engine are high, especially for the large diesel engines commonly found in heavy machinery.

[0003] The work vehicle also includes subsystems that require electrical power. To power these subsystems of the work vehicle, an alternator or generator may be used to utilize a portion of the engine power to generate AC or DC power. The current from the alternator is then inverted to charge the batteries of the work vehicle. Typically, a direct or serpentine belt couples the output shaft of the engine to the alternator to generate the alternating current. The torque requirements for generating current from a running engine are significantly lower than the torque requirements for starting the engine. In order to properly transfer power between the engine and the battery to start the engine and generate electricity, many different components and devices are typically required, causing issues in size, cost, and complexity. Summary of the invention

[0004] The present disclosure provides a combined engine starter and generator arrangement with an integral transmission that can be used, for example, in a work vehicle for cold starting of the engine and generating electricity, thereby serving the dual purpose of an engine starter and an alternator, and in both cases, the power transfer to and from the engine is more robust.

[0005] On the one hand, the present disclosure provides a combined starter-generator device for a work vehicle having an engine. The starter-generator device includes: an electric machine; a gear set configured to receive rotational input from the electric machine and the engine, and to couple the electric machine and the engine in a first power flow direction and a second power flow direction. The gear set is configured to operate in one of a plurality of gear ratios in the first power flow direction, and in at least one gear ratio in the second power flow direction. The starter-generator device also includes a clutch device having at least one active clutch, the at least one active clutch being selectively coupled to the gear set to achieve a gear ratio in the first power flow direction and the second power flow direction. The clutch device also includes at least one drag clutch to apply a drag force to the gear set to decelerate the electric machine.

[0006] In another aspect, the present disclosure provides a transmission system assembly for a work vehicle. The transmission system assembly includes: an engine; an electric machine; a gear set configured to receive rotational input from the electric machine and the engine, and to couple the electric machine and the engine in a first power flow direction and a second power flow direction. The gear set is configured to operate in at least one of a first gear ratio, a second gear ratio, and a third gear ratio in the first power flow direction, and in at least a third gear ratio in the second power flow direction. The transmission system assembly also includes: a clutch device having at least one active clutch, the at least one active clutch selectively coupled to the gear set to achieve a first gear ratio, a second gear ratio, and a third gear ratio in the first power flow direction, and a fourth gear ratio in the second power flow direction. The clutch device also includes at least one drag clutch to apply a drag force to the gear set to decelerate the electric machine. The transmission system assembly also includes: a cam plate configured to convert the at least one active clutch from a disengaged position in which the at least one active clutch is disengaged from the gear set to an engaged position in which the at least one active clutch is coupled to the gear set.

[0007] The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features and advantages will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic side view of an example work vehicle in the form of an agricultural tractor in which the disclosed integrated starter-generator arrangement may be used;

[0009] Figure 2 yes Figure 1 A simplified partial perspective view of an engine of a work vehicle of FIG. 1 , showing an example mounting location of an example starter-generator arrangement;

[0010] Figure 3 An example starter-generator arrangement is provided. Figure 1 A schematic diagram of a portion of a power transmission arrangement of a work vehicle;

[0011] Figure 4 is available in Figure 1 An end perspective view of a power transmission assembly of an example starter-generator arrangement implemented in a work vehicle of;

[0012] Figure 5 is available in Figure 1 A cross-sectional view of a power transmission assembly of an example starter-generator device implemented in a work vehicle;

[0013] Figure 6 is used for the example starter-generator unit Figure 5 a more detailed view of a portion of a power transmission assembly;

[0014] Figure 7 can be combined with Figure 5 An isometric view of a cam plate for an example starter-generator arrangement in a power transmission assembly of FIG.

[0015] Figure 8 is a perspective view of a clutch that may be incorporated into an example starter-generator arrangement Figure 5 In the power transmission components;

[0016] Fig. 9 is an isometric view of a statically determinate plate that may be incorporated into an example starter-generator arrangement. Figure 5 In the power transmission components;

[0017] Fig.10 yes Figure 5 a cross-sectional view of a power transmission assembly of FIG. 1 , which depicts a schematic diagram of a power flow path of an example starter-generator device in a first engine starting mode;

[0018] Fig.11 yes Figure 5 A cross-sectional view of a power transmission assembly depicting a schematic diagram of a power flow path of an example starter-generator device in a second engine starting mode;

[0019] Fig.12 yes Figure 5 A cross-sectional view of a power transmission assembly depicting a schematic diagram of a power flow path of an example starter-generator device in a boost mode;

[0020] Fig.13 yes Figure 5 A cross-sectional view of a power transmission assembly of FIG. 1 depicts a schematic diagram of a power transmission path of an example starter-generator device in a power generation mode;

[0021] Fig.14 is an example starter-generator arrangement in the first engine starting mode Figure 5 A partial cross-sectional view of a power transmission assembly; and

[0022] Fig.15 yes Figure 5 A more detailed partial view of a portion of a power transfer assembly depicting a drag clutch of an example starter-generator arrangement.

[0023] Like reference numerals in the various drawings indicate like elements. DETAILED DESCRIPTION

[0024] One or more example embodiments of the disclosed starter-generator are described below, as shown in the accompanying drawings of schematic diagrams briefly described above. Various modifications to the example embodiments may be anticipated by those skilled in the art.

[0025] As used herein, unless otherwise limited or modified, a list with elements separated by a conjunction (e.g., "and") and also preceded by the phrase "one or more" or "at least one" represents a configuration or arrangement that may include the individual elements of the list or any combination of these elements. For example, "at least one of A, B, and C" or "one or more of A, B, and C" represents the possibility of only A, only B, only C, or any combination of two or more of A, B, and C (e.g., A and B; B and C; A and C; or A, B, and C).

[0026] As used herein, the term "axial" refers to a dimension that is generally parallel to the axis of rotation, axis of symmetry, or centerline of one or more components. For example, in a cylinder or disk having a centerline and opposing generally circular ends or faces, an "axial" dimension may refer to a dimension that extends generally parallel to the centerline between the opposing ends or faces. In some cases, the term "axial" may be used with respect to non-cylindrical (or radially symmetrical) components. For example, an "axial" dimension for a rectangular housing containing a rotating shaft may be considered to be a dimension that is generally parallel to the axis of rotation of the shaft. In addition, the term "radially" as used herein may refer to the dimension or relationship of a component relative to a line extending outward from a shared centerline, axis, or similar reference point, such as in a plane perpendicular to the centerline or axis of a cylinder or disk. In some cases, even if one or both components may not be cylindrical (or radially symmetrical), the components may be considered to be "radially" aligned. Furthermore, the terms "axial" and "radial" (and any derivatives) may encompass directional relationships that differ from being precisely aligned (e.g., tilted) with the true axial and radial dimensions, as long as the relationship is primarily about the corresponding nominal axial or radial dimensions. Additionally, the term "circumferential" may refer to the collective tangential dimension that is perpendicular to the radial and axial dimensions about the axis.

[0027] Many conventional vehicle power systems include an internal combustion engine and / or one or more batteries (or other chemical power sources) that power various components and subsystems of the vehicle. In some electric vehicles, a set of batteries provides power to the entire vehicle, including the drive wheels, to move the vehicle. In hybrid gasoline and electric vehicles, the motive force can alternate between engine power and electric motor power, or the engine power can be supplemented by electric motor power. In other conventional vehicles, the power system is used to initiate engine starting and run the non-driven power system of the vehicle. In the latter case, the vehicle typically has a starter motor that is driven by the vehicle battery to rotate the engine crankshaft to move the pistons in the cylinders. In other cases, the power system can provide a boost to the running engine.

[0028] Some engines (e.g., diesel engines) start combustion by compression of fuel, while other engines rely on spark generators (e.g., spark plugs) powered by batteries. Once the engine is running at sufficient speed, the powertrain can harvest engine power to power the electrical system and charge the battery. Typically, this power collection is performed by an alternator or other type of generator. The alternator converts alternating current (AC) into direct current (DC) that is available to the battery and the vehicle's electrical components by flowing the alternating current through an inverter (e.g., a diode rectifier). Conventional alternators harness power from the engine by coupling the rotor of the alternator to the output shaft of the engine (or a component coupled thereto). Historically, this was achieved using a dedicated belt, but in some more modern vehicles, the alternator is one of several devices connected to the engine (and thereby powered by the engine) via a single "snake" belt.

[0029] In certain applications, such as in certain heavy machinery and work vehicles, conventional arrangements with separate starter and generator components may be disadvantageous. Such separate components require separate housings, which may require separate sealing or shielding from the operating environment and / or occupy separate locations within the limited space of the engine compartment. Other engine compartment layout complexities may also arise.

[0030] One or more example embodiments of an improved vehicle power system are described below, which solves one or more of these (or other) problems in conventional systems. In one aspect, the disclosed system includes a combined or integrated device that performs the engine cranking function of a starter motor and the power generation function of a generator. The device is referred to herein as an integrated starter-generator device ("(integrated starter-generator) ISG" or "starter-generator"). At least in certain embodiments of the system, this term is used herein regardless of the type of power (i.e., AC or DC current) generated by the device. In some embodiments, the starter-generator device can generate power in a manner that a person skilled in the art would consider a "generator" device that directly generates direct current. However, as used herein, the term "generator" should mean the generation of static or alternating polarity power (i.e., AC or DC). Therefore, in the special case of a starter-generator device, the power generation function is similar to a conventional AC generator, and it generates AC power, which is then rectified to DC power inside or outside the starter-generator device.

[0031] In certain embodiments, the starter-generator device may include a direct mechanical power coupling to the engine, thereby avoiding the use of a belt between the engine and the starter-generator device. For example, the starter-generator device may include a power transfer assembly having a gear set within its housing that is directly coupled to the output shaft of the engine. The gear set can take any of a variety of forms, including an arrangement having meshing spur gears or other gears and an arrangement having one or more planetary gear sets. The power transfer assembly can achieve a large gear reduction ratio so that a single electric machine (i.e., a motor or generator) can be used and operated at an appropriate speed to perform one or more types of engine starting and generate electricity. The direct power coupling between the starter-generator device and the engine can improve system reliability, cold start performance, and power generation of the system.

[0032] In addition, in certain embodiments, the starter-generator device may have a power transmission assembly that automatically and / or selectively changes the gear ratio (i.e., converts between power flow paths with different gear ratios). For example, the power transmission assembly may include one or more engagement components that are engaged or disengaged automatically or on command. For example, a passive engagement component, such as a one-way clutch (e.g., a roller clutch or a sprag clutch), can be used to achieve power transmission through the power flow path in the engine starting direction; an active engagement component, such as a friction clutch assembly, can be used to achieve power transmission through other power flow paths. In this way, a two-way or other clutch (or other) configuration can be adopted to perform crankshaft starting and power generation functions using appropriate control hardware. Due to the bidirectional nature of the power transmission assembly, the power transmission belt device can be implemented using only a single belt tensioner, thereby providing a relatively compact and simple assembly. In addition to providing torque in two different power flow directions, the gear set can also be constructed and arranged to provide power transmission from the electric machine to the engine at one of two different speeds, for example, according to different gear ratios. The choice of speed can provide additional functionality and flexibility for the power transmission assembly.

[0033] In one example, the combined starter-generator may further include a dog clutch arrangement having a first clutch, a second clutch, and a third clutch arranged annularly and concentrically, each clutch having clutch teeth that selectively engage the gear set when the corresponding clutch is repositioned from the disengaged position to the engaged position. The clutch may be supported by a static plate between the clutch and the gear set to receive a reaction force, thereby providing the clutch with a certain degree of flexibility.

[0034] The combined starter-generator also includes a cam plate having cam teeth that can be pivoted to push the clutch into an engaged position based on an angular position. The cam teeth that engage the respective clutches can be radially and circumferentially offset relative to each other. In some examples, the clutch can include an opening to accommodate the cam teeth in the disengaged position.

[0035] In some examples, the combined starter-generator clutch may further include a drag clutch that may be at least partially mounted on the input shaft to decelerate the electric machine. The drag clutch may be preloaded by a spring to generate a predetermined amount of drag force, such as approximately 10 Nm. The drag force serves to facilitate synchronization during speed or direction changes.

[0036] Each embodiment is discussed in more detail below.

[0037] Referring to the accompanying drawings, an exemplary work vehicle power system as a power transmission system component will be described in detail. It will be apparent from the discussion herein that the disclosed system can be advantageously used in a variety of settings and with a variety of machines. For example, referring now to Figure 1 , powertrain (or drivetrain assembly) 110 may be included in work vehicle 100, which is depicted as an agricultural tractor. However, it will be appreciated that other configurations are possible, including configurations with work vehicle 100 as a different kind of tractor, or as a work vehicle used in other aspects of the agricultural industry or for the construction and forestry industries (e.g., harvesters, fellers, graders, etc.). It will also be appreciated that aspects of powertrain 110 may also be used in non-work vehicles and non-vehicle applications (e.g., fixed-position installations).

[0038] Briefly, work vehicle 100 has a main frame or chassis 102 supported by ground engaging wheels 104, at least the front wheels of which are steerable. Chassis 102 supports a power system (or device) 110 and a cab 108 in which an operator interface and controls (e.g., various joysticks, toggle levers, buttons, touch screens, keyboards, speakers and microphones associated with a voice recognition system) are provided.

[0039] As schematically shown, power system 110 includes engine 120, integrated starter-generator device 130, battery 140, and controller 150. Engine 120 may be an internal combustion engine or other suitable power source adapted to be coupled via wheels 104 to propel work vehicle 100 autonomously or based on commands from an operator. Battery 140 may represent any one or more suitable energy storage devices that may be used to provide power to various systems of work vehicle 100.

[0040] The starter-generator device 130 couples the engine 120 to the battery 140 so that the engine 120 and the battery 140 can selectively interact in at least four modes. In the first (or engine cold start) mode, the starter-generator device 130 converts electricity from the battery 140 into mechanical power to drive the engine 120 at a higher speed, for example, during a relatively cold engine start. In the second (or engine hot start) mode, the starter-generator device 130 converts electricity from the battery 140 into mechanical power to drive the engine 120 at a relatively low speed, for example, during a relatively hot engine start. In the third (or boost) mode, the starter-generator device 130 converts electricity from the battery 140 into mechanical power to drive the engine 120 to provide engine boost. In the fourth (or power generation) mode, the starter-generator device 130 converts mechanical energy from the engine 120 into electrical energy to charge the battery 140. Additional details about the operation of the starter-generator device 130 during the engine start mode, boost mode, and power generation mode are as follows.

[0041] As described above, the controller 150 can be considered as part of the power system 110 to control various aspects of the work vehicle 100, especially the characteristics of the power system 110. The controller 150 can be a work vehicle electronic controller unit (ECU) or a dedicated controller. In some embodiments, the controller 150 can be configured to receive input commands from various sensors, units and systems onboard or remote from the work vehicle 100 via a human-machine interface or operator interface (not shown) and interact with the operator; in response, the controller 150 generates one or more types of commands to be implemented by the power system 110 and / or various systems of the work vehicle 100.

[0042] In general, the controller 150 may be configured as a computing device having an associated processor device and memory architecture, and may be configured as a hydraulic, electric or electro-hydraulic controller, etc. In this way, the controller 150 may be configured to perform various computing and control functions for the power system 110 (and other machines). The controller 150 may be in electronic, hydraulic or other communication with various other systems or devices of the work vehicle 100. For example, the controller 150 may be in electronic or hydraulic communication with various actuators, sensors and other devices inside the work vehicle 100 (or outside the work vehicle 100) including various devices associated with the power system 110. In general, the controller 150 generates command signals based on operator input, operating conditions, and routines and / or schedules stored in memory. For example, the operator may provide input to the controller 150 via an operator input device that indicates an appropriate mode, or at least partially defines the operating conditions under which the controller 150 selects the appropriate mode. In some examples, the controller 150 may additionally or alternatively operate autonomously without human input. The controller 150 may communicate with other systems or devices (including other controllers) in various known manners, including via a CAN bus (not shown), via wireless or hydraulic communication means, or other manners.

[0043] In addition, the power system 110 and / or the work vehicle 100 may include a hydraulic system 152 having one or more electro-hydraulic control valves (e.g., solenoid valves) that facilitate hydraulic control of various vehicle systems, particularly various aspects of the starter-generator arrangement 130. The hydraulic system 152 may also include various pumps, lines, hoses, conduits, tanks, etc. The hydraulic system 152 may be electrically activated and controlled based on signals from the controller 150. In one example, and as discussed in more detail below, the hydraulic system 152 may be used to engage and / or disengage a clutch within the starter-generator arrangement 130, for example, by applying and releasing hydraulic pressure based on signals from the controller 150 for one or more clutch actuators. Other mechanisms for controlling such a clutch may also be provided.

[0044] In one example, the starter-generator device 130 includes a power transmission assembly (or transmission) 132, an electric machine or electric motor 134, and an inverter / rectifier device 136, each of which can be operated according to a command signal from a controller 150. The power transmission assembly 132 enables the starter-generator device 130 to engage with the engine 120, particularly via the crankshaft (or auxiliary drive shaft or other engine power transfer element) 122 of the engine 120. The power transmission assembly 132 may include one or more gear sets in various configurations to provide suitable power flow and gear reduction, as described below. The power transmission assembly 132 is variably connected to the electric machine 134 in two different power flow directions, so that the electric machine 134 operates as an electric motor during engine starting and boosting modes, and operates as a generator during power generation mode. In one example discussed below, the power transmission assembly 132 is coupled to the electric machine 134 via a power transmission belt device. This arrangement, along with the multiple gear ratios provided by the power transfer assembly 132, allows the electric machine 134 to operate within an optimal speed and torque range in both directions of power flow. The inverter / rectifier device 136 enables the starter-generator device 130 to be connected to the battery 140, for example, by direct hard wiring or a vehicle power bus 142. In one example, the inverter / rectifier device 136 converts alternating current (DC) electricity from the battery 140 into direct current (AC) electricity during the engine starting mode, and rectifies the DC electricity into AC electricity in the power generation mode. In some embodiments, the inverter / rectifier device 136 can be a separate component rather than being incorporated into the starter-generator device 130. Although not shown, the power system 110 can also include a suitable voltage regulator that is incorporated into the starter-generator device 130 or as a separate component.

[0045] Brief reference Figure 2 , Figure 2 A simplified partial isometric view of an example mounting location of the starter-generator assembly 130 relative to the engine 120 is shown. In this example, the integrated starter-generator assembly 130 is mounted directly and compactly to the engine 120 so as not to significantly protrude from the engine 120 (thereby not expanding the spatial extent of the engine compartment) or interfere with various lines and access points (e.g., oil lines and oil filler ports, etc.). It is worth noting that the starter-generator assembly 130 can generally be mounted on or near the engine 120 in a manner suitable for coupling to engine power transmission elements (e.g., such as Figure 1 The position of the crankshaft 122) is shown.

[0046] In addition, refer to Figure 3 , Figure 31 is a simplified schematic diagram of a power transmission belt device 200 between the power transmission assembly 132 of the starter-generator device 130 and the electric machine 134. It should be noted that Figure 2 and 3 One example physical integration or layout configuration of the starter-generator arrangement 130 is depicted. Other arrangements may be provided.

[0047] The power transmission assembly 132 is mounted to the engine 120 and can be supported by the reaction plate 124. As shown, the power transmission assembly 132 includes: a first power transmission element 133, which is rotatably coupled to a suitable drive element of the engine 120 (e.g., Figure 1 and a second power transmission element 135 in the form of a shaft extending on the opposite side of the power transmission assembly 132 relative to the first power transmission element 133. Similarly, the electric machine 134 is mounted on the engine 120 and includes another power transmission element 137.

[0048] The power transmission belt device 200 includes a first pulley 210 disposed on the second power transmission element 135 of the power transmission assembly 132, a second pulley 220 disposed on the power transmission element 137 of the electric machine 134, and a belt 230 rotatably connecting the first pulley 210 and the second pulley 220 for common rotation. As described in more detail below, during the engine starting mode, the electric machine 134 pulls the belt 230 to rotate the pulleys 210, 220 in the first clock direction D1 to drive the power transmission assembly 132 (thereby driving the engine 120); during the boost mode, the electric machine 134 pulls the belt 230 to rotate the pulleys 210, 220 in the second clock direction D2 to drive the power transmission assembly 132 (thereby driving the engine 120); in the power generation mode, the power transmission assembly 132 causes the engine 120 to pull the belt 230 and rotate the pulleys 210, 220 in the second clock direction D2 to drive the electric machine 134.

[0049] As a result of the bidirectional configuration, the power transmission belt device 200 may include only a single belt tensioner 240 to apply tension to a single side of the belt 230 in both directions D1, D2. Using a single belt tensioner 240 to tension the belt 230 is advantageous because it reduces parts and reduces complexity compared to designs that require multiple belt tensioners. As described below, the bidirectional configuration and the associated simplified power transmission belt device 200 are achieved by the bidirectional nature of the gear set in the power transmission assembly 132. In addition, the difference in the circumference of the first and second pulleys 210, 220 can provide a change in the transmission ratio between the power transmission assembly 132 and the electric machine 134. In one example, the power transmission belt device 200 can provide a transmission ratio between 3:1-5:1, and in particular a ratio of 4:1.

[0050] In one example, Figure 4 An engine-side isometric view of a power transfer assembly 132 that may be implemented in a starter-generator arrangement 130 is depicted. As shown, the power transfer assembly 132 includes a housing 302 having a rotatable housing element 303 that, in this example, serves as a power transmission element of the power transfer assembly 132 and engages with a corresponding power transmission element (e.g., crankshaft 122) of the engine 120. A fixed housing mount 304 supports the housing 302 on the engine 120 ( Figure 4 In this example, the housing mount 304 includes three support legs, a first end of which extends from a side of the housing 302 opposite the engine 120 and a second end of which is mounted to the engine 120 ( Figure 4 not shown).

[0051] exist Figure 5 The power transmission assembly 132 is further shown in the cross-sectional view of FIG. As shown, the power transmission assembly 132 can be considered as a unit having an annular housing 302, which is configured to accommodate the various components of the power transmission assembly 132. Figure 5 1, a first side 306 of the power transfer assembly 132 faces the electric machine 134, and a second side 308 of the power transfer assembly 132 faces the engine 120. The housing 302 also includes a fixed housing element 305 positioned between the rotatable housing element 303 and the housing mount 304. The housing mount 304 and the fixed housing element 305 are positioned relative to the rotatable housing element 303 on a bearing 307 that allows relative rotation during operation.

[0052] At the first side 306, the power transfer assembly 132 includes an input shaft 310 that is coupled to the electric machine 134 (eg, via the power transmission belt arrangement 200). In some examples, the input shaft 310 may be directly coupled to the power transmission assembly 132 described above. Figure 1 and Figure 2 132; however, in other examples, the input shaft 310 can be coupled via an intermediate component such as a flange or boss. It should be noted that although the shaft 310 is described as an "input" shaft, it can transmit power to and from the power transmission assembly 132, depending on the mode, as described below. The input shaft 310 generally extends through the power transmission assembly 132 to define a primary axis of rotation 300.

[0053] The power transfer assembly 132 generally includes a planetary gear set 320. As described below, the planetary gear set 320 is a two-stage planetary gear set and generally engages the power transfer assembly 132 with the electric machine 134 (e.g., via the power transmission belt device 200) and the engine 120 (e.g., via a direct coupling to the crankshaft 122 of the engine 120). In some embodiments, the input shaft 310 can be considered to be part of the planetary gear set 320. Although one example configuration of the planetary gear set 320 is described below, other embodiments can have different configurations.

[0054] Additional references Figure 6 , which is Figure 5 . The planetary gear set 320 includes a first stage sun gear 322 mounted for rotation on the input shaft 310. The gear 322 includes a plurality of teeth or splines that mesh with a set of first stage planet gears 324 surrounding the first stage sun gear 322. In one example, the first stage planet gears 324 include a single row of one or more planet gears arranged circumferentially, although other embodiments may include multiple rows stacked radially with each row having an odd number of planet gears.

[0055] The first stage planet gears 324 are supported by a first stage planet gear carrier 326 that surrounds the first stage sun gear 322 and the input shaft 310 and is at least partially formed by radially extending and axially facing first and second carrier plates 328, 330. The first stage carrier plates 328, 330 include a row of mounting locations for accommodating shafts that extend through and support the first stage planet gears 324 for rotation. Thus, in this arrangement, each planet shaft forms a separate axis of rotation for each first stage planet gear 324, and the first stage planet gear carrier 326 enables a group of first stage planet gears 324 to rotate together around the first stage sun gear 322.

[0056] The gear set 320 further includes a ring gear 332 surrounding the first stage sun gear 322 and the first stage planetary gears 324. The ring gear 332 includes radially inner teeth that mesh with the teeth of the first stage planetary gears 324. In this way, the first stage planetary gears 324 extend between the first stage sun gear 322 and the ring gear 332 and mesh with them. In some embodiments, a ring gear cover 333 can be installed inside the ring gear 332. The ring gear cover 333 is used to at least partially enclose the gear set 320 in the housing 302.

[0057] In practice, the ring gear 332 is integral with the rotatable housing element 303, which is positioned on the bearing 307 as described above to rotate relative to the fixed housing mount 304. Relative to the planetary gear set 320, the ring gear 332 can serve as a power transmission element 133 relative to the engine 120. In particular, the ring gear 332 includes a plurality of castellations 336 that extend axially around the circumference of the axial surface facing the engine 120. The ring gear 336 engages and rotatably fixes the ring gear 332 to the crankshaft 122 of the engine 120. The ring gear 332 can be considered an output element of the power transfer assembly 132. However, similar to the input shaft 310, the ring gear 332 can receive rotational input in both power flow directions.

[0058] The gear set 320 further includes a second stage sun gear 340 that is generally hollow and cylindrical, extending between first and second ends 342, 344 and surrounding the input shaft 310. The first stage planet gear carrier 326 has splines that engage or are otherwise fixed to the second stage sun gear 340 at a location proximate to the first end 342. In addition, the second stage sun gear 340 may include a series of splines that mesh with a set of second stage planet gears 346. The second stage planet gears 346 are supported by a second stage planet gear carrier 348, which is formed by first and second carrier plates 350, 352. The second stage planet gears 346 are positioned to additionally mesh with the ring gear 332. The second stage planet gears 346 each have an axis extending between the two carrier plates 350, 352 that enables each planet gear 346 to rotate about a respective axis relative to the planet gear carrier 348. Thus, the second stage planet gears 346 are located between and mesh with the second stage sun gear 340 and the ring gear 332. In some examples, each second stage planet gear 346 has a different number of teeth than each corresponding first stage planet gear 324, while in other examples, each second stage planet gear 346 has the same number of teeth as each corresponding first stage planet gear 328.

[0059] As will now be described in greater detail, the power transfer assembly 132 additionally includes a clutch device 360 ​​that is configured to selectively engage and disengage various components of the planetary gear set 320 to vary power flow through the power transfer assembly 132 .

[0060] Generally, the clutch device 360 ​​includes a cam actuator or plate 370, an actuator assembly 380, a first (or low-range) clutch 390, a second (or mid-range) clutch 400, a third (or high-range) clutch 410, and as described below, each clutch 390, 400, 410 can be switched between an engaged position and a disengaged position. In this way, the clutches 390, 400, 410 can be considered as "speed-changing" clutches that are actively actuated to change the power flow within the power transmission assembly 132.

[0061] In one example, the actuator assembly 380 operates to pivot the cam plate 370, which in turn selectively moves the clutches 390, 400, 410 from the disengaged position to the engaged position under the support of the static plate 420 to engage the gear set 320. Although not shown, one or more springs may be provided to maintain the position of the clutches 390, 400, 410 when not in the engaged position and / or to return the clutches 390, 400, 410 to the disengaged position when the cam plate 370 is subsequently repositioned. For example, a first spring (not shown) is located between the low-range clutch 390 and the static plate 420, a second spring (not shown) is located between the mid-range clutch 400 and the static plate 420, and a third spring (not shown) is located between the high-range clutch 410 and the static plate 420 to bias the clutches 390, 400, 410 away from the static plate 420 in the disengaged position. In effect, each of the clutches 390, 400, 410 operates as a "cam-actuated, spring-released" device. In some examples, the clutch arrangement 360 may further include a drag clutch 440 that also affects power flow through the power transfer assembly 132. As described in more detail below following discussion of other aspects of the clutch arrangement 360, the drag clutch 440 may be considered a passive clutch.

[0062] As schematically shown, the gear set 320 includes a plurality of engagement elements 430, 432, 434 that enable interaction between various components of the gear set 320 and the clutches 390, 400, 410. Generally, as described below, the engagement elements 430, 432, 434 are configured as slots, locks, or pockets that interact with the clutches 390, 400, 410. In some examples, one or more of the engagement elements 430, 432, 434 can be bidirectional, having two inclined walls or two vertical walls, or one or more of the engagement elements 430, 432, 434 can be designed to have a single orientation, for example, having an inclined wall as opposed to a vertical wall.

[0063] The first engagement element 430 may be in the form of one or more slots or locks on the second stage planet gear carrier 348. The first engagement element 430 operates as discussed below to receive a portion of the low range clutch 390, thereby locking the second stage planet gear carrier 348 to the fixed housing element 305, i.e., grounding the second stage planet gear carrier 348 and preventing rotation.

[0064] The second engagement element 432 may be in the form of one or more slots or locks on the second stage sun gear 340. The second engagement element 432 operates as discussed below to receive a portion of the midrange clutch 400 to lock the second stage sun gear 340 to the fixed housing element 305, i.e., to ground the second stage sun gear 340 and prevent rotation.

[0065] The third engagement element 434 is configured to selectively couple and disengage the first stage sun gear 322 with the second stage sun gear 340 via the input shaft 310. In one example, the third engagement element 434 includes one or more shifting or sliding elements that can be repositioned between a first position that enables the second stage sun gear 340 to rotate independently relative to the input shaft 310 (which is rotationally coupled to the first stage sun gear 322) and a second position that connects the second stage sun gear 340 with the input shaft 310 (and thus the first stage sun gear 322) for common rotation. As discussed in more detail below, actuating the high gear clutch 410 to the engaged position moves the third engagement element 434 to the second position, locking the second stage sun gear 340 to the first stage sun gear 322 via the input shaft 310. When the high gear clutch 410 returns to the disengaged position, the third engagement element 434 returns to the first position (e.g., by means of a spring), disengaging the second stage sun gear 340 from the first stage sun gear 322 and the input shaft 310.

[0066] Brief reference Figure 7, which is an isometric view of the cam plate 370 removed from the power transmission assembly 132. As shown, the cam plate 370 is generally disc-shaped or annular, having a first face 371 and a second face 372 defining an outer periphery 374 and a central mounting hole 375. The cam plate 370 is mounted within the power transmission assembly 132 and is configured to pivot about an axis coaxial with the main axis of the main shaft through an appropriate range, such as approximately 30°. The cam plate 370 includes a series of cam teeth 376, 377, 378 at specified circumferential and radial positions to selectively interact with the clutches 390, 400, 410 in the axial direction according to the angular position of the cam plate 370. In this example, the cam teeth 376, 377, 378 include: a first row of cam teeth 376, which are located in a first circumferential row at a common radial distance, and the first row of cam teeth interacts with the low-speed clutch 390; a second row of cam teeth 377, which are located in a second circumferential row at a common radial distance, and the second row of cam teeth interacts with the mid-speed clutch 400; and a third row of cam teeth 378, which are located in a third circumferential row at a common radial distance, and the third row of cam teeth interacts with the high-speed clutch 410. As shown, the rows of cam teeth 376, 377, 378 have respective circumferential positions relative to the other rows of teeth 376, 377, 378. In other words, the cam teeth 376, 377, 378 in each row are radially offset from the cam teeth 376, 377, 378 in the other rows. In this way, the cam plate 370 can be positioned to selectively engage each clutch 390, 400, 410, as described in more detail below. In some examples, each tooth 376, 377, 378 can have a shape that facilitates engagement and disengagement with a corresponding clutch 390, 400, 410. For example, each tooth 376, 377, 378 can have an inclined side and a generally perpendicular side relative to the face 371 of the cam plate 370. The inclined side provides smoother movement, especially when disengaging. In addition, each cam tooth 376, 377, 378 can have a relatively flat top surface that provides a larger surface to engage with the clutch 390, 400, 410, as described below.

[0067] Briefly, again refer to Figure 6, the cam plate 370 can be pivoted by the actuator assembly 380. In one example, the actuator assembly 380 includes a flange 382 extending from the second face 372 of the cam plate 370 and terminating in a piston element 384, which is positioned within a cylinder element 386. The cylinder element 386 of the actuator assembly 380 is arranged in the fixed housing element 305 at a position close to the housing mount 304, and is fluidly coupled to a hydraulic circuit (not shown) having a hydraulic source, a control valve, a pump, and other components operably coupled to the controller 150. By changing the hydraulic pressure in the cylinder element 386, the piston element 384 is repositioned, which in turn is used to reposition the cam plate 370. Therefore, the actuator assembly 380 can be controlled by changing the fluid pressure in the cylinder element 386 through the hydraulic circuit based on a command from the controller 150. In this way, the controller 150 can command the position of the cam plate 370 to achieve a desired operating mode. Other types of actuator assemblies may be provided to reposition the cam plate 370 , including linear actuators.

[0068] Reference now Figure 8 , Figure 8 1 is an isometric view of the clutches 390, 400, 410 removed from the power transfer assembly 132. In one example, the clutches 390, 400, 410 can be considered to be "dog" type clutches. As shown, the clutches 390, 400, 410 are generally configured as concentric rings. The low-range clutch 390 is the largest and is formed by the first and second faces 391, 392 and the outer and inner circumferences 393, 394 that define the clutch ring base 395. The mid-range clutch 400 is located between the low-range clutch 390 and the high-range clutch, and the mid-range clutch 400 is formed by the first and second faces 401, 402 and the outer circumference 403 and the inner circumference 404 that define the clutch ring base 405. The high-range clutch 410 is the smallest, is radially arranged inside the mid-range clutch 400, and is formed by the first and second faces 411, 412 and the outer circumference 413 and the inner circumference 414 that define the clutch ring base 415. The clutches 390, 400, 410 may be mounted together on a main shaft extending from the stationary housing element 305 and configured to each move axially but remain stationary in circumferential and radial dimensions.

[0069] Each clutch 390, 400, 410 also defines a series of clutch teeth 396, 406, 416 extending generally perpendicularly from the respective first clutch face 391, 401, 411 of the ring base 395, 405, 415 and the clutch opening 397 of the ring base 395, 405, 415, with each clutch tooth circumferentially adjacent to a respective one of the clutch teeth 396, 406, 416. In this embodiment, four clutch teeth 396, 406, 416 and four clutch openings 397, 407, 417 are provided for each clutch 390, 400, 410. Other embodiments may have a greater or lesser number of teeth and / or openings. The clutch teeth 396 , 406 , 416 may have a slight bevel or angled shape at the intersection of the respective tooth 396 , 406 , 416 and the base 395 , 405 , 415 , which facilitates engagement and disengagement of the clutch 390 , 400 , 410 .

[0070] In one embodiment, each of the clutches 390, 400, 410 may be formed from a single piece of material that is stamped to form the clutch teeth 396, 406, 416 and the clutch openings 397, 407, 417. As described in more detail below, the stamping process enables the realization of a dog clutch 390, 400, 410 in which: 1) the clutch teeth 396, 406, 416 are configured to engage the gear set 320; 2) the shape of the teeth 396, 406, 416 provides a ramp that facilitates engagement; 3) the openings 397, 407, 417 provide clearance for the cam plate 370 when disengaged; and 4) the structure of each clutch 390, 400, 410 enables load sharing during operation.

[0071] In this example, the clutch teeth 396 and clutch opening 397 of the low range clutch 390 are generally radially aligned with the corresponding clutch teeth 406 and clutch opening 407 of the mid range clutch 400, which in turn are generally radially aligned with the corresponding clutch teeth 416 and clutch opening 417 of the high range clutch 410. As described below, the clutches 390, 400, 410 are supported so that the clutches 390, 400, 410 can have a certain degree of flexibility to accommodate relative movement within the power transfer assembly 132.

[0072] As described above, the clutches 390, 400, 410 are generally concentrically arranged and rotationally fixed. However, each clutch 390, 400, 410 is arranged to be axially shifted from a disengaged position to an engaged position by the cam plate 370 due to the concentric arrangement, and then returned to the disengaged position. In the engaged position, the clutch teeth 396, 406, 416 of the clutch 390, 400, 410 being shifted selectively engage the gear set 320. In other words, the cam plate 370 has an angular position in which the cam teeth 376, 377, 378 are received by the clutch openings 397, 407, 417, which corresponds to a disengaged clutch position, and other angular positions in which the cam teeth 376, 377, 378 contact the corresponding second face 392, 402, 412 of the selected clutch 390, 400, 410 to axially push the corresponding clutch 390, 400, 410 into an engaged position to engage the corresponding clutch teeth 396, 406, 416 with the engagement elements 430, 432, 434 of the gear set 320 to change the power flow. Additional details and operational examples will be provided below.

[0073] Reference now Fig. 9 , Fig. 9 4 is an isometric view of the static plate 420 removed from the power transmission assembly 132. The static plate 420 is generally disc-shaped, with a first face 421 oriented toward the gear set 320 and a second face 422 oriented toward the clutches 390, 400, 410. The static plate 420 defines a plurality of slots 424, 425, 426 in rows at designated radial and circumferential positions. In particular, the static plate 420 includes: a circumferential first row of slots 424, which are positioned to accommodate the clutch teeth 396 of the low-range clutch 390 when the low-range clutch 390 is in the engaged position; a circumferential second row of slots 425, which are positioned to accommodate the clutch teeth 406 of the mid-range clutch 400 when the mid-range clutch 400 is in the engaged position; and a circumferential third row of slots 426, which are positioned to accommodate the clutch teeth 416 of the high-range clutch 410 when the high-range clutch 410 is in the engaged position. During operation, the stationary plate 420 is stationary, without rotational or axial movement. As described in more detail below, the stationary plate 420 is used to accept the reaction loads generated by the engagement between the clutch 390, 400, 410 and the engagement element 430, 432, 434 of the gear set 320. This also enables the clutch 390, 400, 410 to have a certain degree of flexibility.

[0074] As described above, the power transmission assembly 132 can be operated to selectively function in one of four different modes, including: a first or engine cold start mode, in which the power transmission assembly 132 transfers power from the battery 140 to the engine 120 at a first gear ratio; a second or engine hot start mode, in which the power transmission assembly 132 transfers power from the battery 140 to the engine 120 at a second gear ratio; a third or boost mode, in which the power transmission assembly 132 transfers power from the battery 140 to the engine 120 at a third gear ratio; and a power generation mode, in which the power transmission assembly 132 transfers power from the engine 120 to the battery 140 at a fourth gear ratio, which in this example is equal to the third gear ratio. In contrast, the engine start mode is a relatively low speed and relatively high torque output, while the boost and power generation modes are relatively high speeds and relatively low torque outputs. In this way, the power transmission assembly 132 and the power transmission belt device 200 are bidirectional and have different gear ratios to transmit power in different power flow directions and along different power flow paths depending on the mode. Reference is made below Figure 10-13 The power flow paths in different modes are described, where arrows are provided to schematically represent the power flow.

[0075] Reference now Fig.10 , which is a diagram of the power transmission assembly 132 in the engine cold start mode, and is marked with arrows representing the power flow path. In the following discussion, reference is also made to Figure 7-9 as well as Fig.14 , Fig.14 is a cross-sectional view of a portion of the power transfer assembly 132 in an engine cold start mode.

[0076] In this example, the actuator assembly 380 commanded by the controller 150 is used to pivot the cam plate 370 to a first angular position. In this position, the first cam tooth 376 of the cam plate 370 engages the second face 392 of the low-range clutch 390 to move the low-range clutch 390 to the engaged position. Also in the first angular position, the second cam tooth 377 of the cam plate 370 is received within the opening 407 of the mid-range clutch 400, and the third cam tooth 378 of the cam plate 370 is received within the opening 417 of the high-range clutch 410, thereby causing the mid-range clutch 400 and the high-range clutch 410 to remain in the disengaged position. As the first cam tooth 376 of the cam plate 370 engages the second face 392 of the low-range clutch 390, the low-range clutch 390 is urged axially toward the gear set 320. When the low-range clutch 390 is urged in this direction, the clutch teeth 396 of the low-range clutch 390 extend through the first slots 424 in the stationary plate 420 and into the first engagement elements 430 on the second stage planetary gear carrier 348, resulting in the engaged position of the low-range clutch 390. In the disengaged position, the clutch teeth 406 of the mid-range clutch 400 and the clutch teeth 416 of the high-range clutch 410 can be at least partially positioned within the slots 425, 426 of the stationary plate 420, although in some embodiments, the clutch teeth 406, 416 of the disengaged clutches 400, 410 can also be completely retained outside the stationary plate 420.

[0077] The clutch teeth 396 are positioned through the static plate 420 into the first engagement element 430 of the second stage planetary gear carrier 348 to ground and prevent the second stage planetary gear carrier 348 from rotating. In this position, the static plate 420 supports the low gear clutch 390 by receiving the reaction force from the second stage planetary gear carrier 348. Fig.14 The view of FIG. 3 specifically depicts the cam teeth 376 of the cam plate 370 axially moving the low range clutch 390 such that the clutch teeth 396 extend through the slots 424 of the stationary plate 420 and into the engagement elements 430 of the second stage planetary gear carrier 348. Fig.14 It is not visible in the drawing, but the cam teeth 377, 378 of the cam plate 370 are received by the openings 407, 417 in the mid-range and high-range clutches 400, 410, so that these clutches 400, 410 remain disengaged.

[0078] When the second stage planetary gear carrier 348 is grounded, the power transfer assembly 132 may be operated in an engine cold start mode. In the engine cold start mode, the engine 120 may be initially inactive and an operator in the cab 108 of the work vehicle 100 activates the ignition to energize the electric machine 134 to operate as a motor. Figure 3, the electric machine 134 rotates the pulley 220 in the first clock direction D1, thereby driving the belt 230 and the pulley 210 in the first clock direction D1. The pulley 210 drives the element 135 in the first clock direction D1, thereby driving the input shaft 310. The rotation of the input shaft 310 drives the rotation of the first stage sun gear 322, and the rotation of the first stage sun gear 322 in turn drives the rotation of the first stage planetary gears 324. The first stage planetary gears 324 drive the first stage planetary gear carrier 326, which is splined to the second stage sun gear 340 as described above. As a result, the first stage planetary gear carrier 326 drives the second stage sun gear 340 and thus drives the second stage planetary gears 346. As described above, the second stage planetary gear carrier 348 is grounded by the low gear clutch 390. In this way, the rotation of the first stage planetary gears and the second stage planetary gears 324, 346 operates to drive the ring gear 332. The first-stage planetary gears and the second-stage planetary gears 324, 346 in the power flow path are odd numbers (e.g., 1) in the radial direction, and the first-stage planetary gears and the second-stage planetary gears 324, 346 drive the ring gear 332 in the opposite direction (e.g., the second clock direction D2) relative to the first-stage sun gears and the second-stage sun gears 322, 340 rotating in the first clock direction D1. As described above, the ring gear 332 is used as a power transmission element 133 to interface with the crankshaft 122 of the engine 120 to drive and facilitate engine starting. In fact, during the engine cold start mode, the power transmission assembly 132 operates in a configuration of sun gear input and ring gear output.

[0079] In one example, the power transfer assembly 132 provides a 15:1 gear ratio in the power flow direction of the engine cold start mode. In other embodiments, other gear ratios (e.g., 10:1 to 30:1) may be provided. Considering the 4:1 gear ratio from the power transmission belt device 200, during the engine cold start mode, for the starter-generator device 130 between the electric machine 134 and the engine 120, a final 60:1 gear ratio (e.g., about 40:1 to about 120:1) can be achieved. Thus, for example, if the electric machine 134 rotates at 10,000 RPM, the crankshaft 122 of the engine 120 rotates at about 100-150 RPM. In one example, the power transfer assembly 132 can transmit a torque of about 3000 Nm to the engine 120. Therefore, the electric machine 134 can have a normal operating speed with a relatively low speed and a high torque output for engine cold start.

[0080] Reference now Fig.11 , Fig.11 The power transmission assembly 132 is similar to Figure 5 A partial cross-sectional view with arrows marking the direction of power flow. Fig.11 The power flow arrows of 130 particularly depict operation of the power transfer assembly 132 in the engine hot start mode.

[0081] In this example, the actuator assembly 380 commanded by the controller 150 is used to pivot the cam plate 370 to the second angular position. In this position, the second cam tooth 377 of the cam plate 370 engages the second face 402 of the mid-range clutch 400 to place the mid-range clutch 400 in the engaged position. Also in the second angular position, the first cam tooth 376 of the cam plate 370 is received in the opening 397 of the low-range clutch 390, and the third cam tooth 378 of the cam plate 370 is received in the opening 417 of the high-range clutch 410, thereby causing the low-range clutch 390 and the high-range clutch 410 to remain in the disengaged position. Since the second cam tooth 377 of the cam plate 370 engages the second face 402 of the mid-range clutch 400, the mid-range clutch 400 is pressed toward the gear set 320. When the mid-range clutch 400 is urged in this direction, the clutch teeth 406 of the mid-range clutch 400 extend through the second slots 425 in the stationary plate 420 and enter the second engagement element 432 on the second stage sun gear 340, resulting in the engaged position of the mid-range clutch 400. In the disengaged position, the teeth 396 of the low-range clutch 390 and the clutch teeth 416 of the high-range clutch 410 may be at least partially positioned within the slots 424, 426 of the stationary plate 420, although in some embodiments, the clutch teeth 396, 416 of the disengaged clutches 390, 410 may be completely retained outside of the stationary plate 420.

[0082] The clutch teeth 406 of the mid-range clutch 400 are positioned through the static plate 420 into the second engagement element 432 of the second-stage sun gear 340 to ground and prevent the second-stage sun gear 340 from rotating. In this position, the static plate 420 serves to receive the reaction force from the second-stage sun gear 340. In addition, since the first-stage planetary gear carrier 326 is splined to the second-stage sun gear 340, the engagement of the mid-range clutch 400 also operates to ground the first-stage planetary gear carrier 326.

[0083] In the engine hot start mode, the engine 120 may be initially inactive or active. Regardless, the controller 150 energizes the electric machine 134 to operate as an electric motor. Figure 3 The electric machine 134 rotates the pulley 220 in the first clock direction D1, thereby driving the belt 230 and the pulley 210 in the first clock direction D1. The pulley 210 drives the element 135 in the first clock direction D1, thereby driving the input shaft 310.

[0084] Since the first stage sun gear 322 is mounted on the input shaft 310, the rotation of the input shaft 310 also rotates the first stage sun gear 322. The rotation of the first stage sun gear 322 in turn drives the rotation of the first stage planetary gears 324. Since the first stage planetary gear carrier 326 and the second stage sun gear 340 are grounded, the rotation of the first stage planetary gears 324 drives the rotation of the ring gear 332.

[0085] Since the number of the first-stage planetary gears 324 in the power flow path is an odd number (e.g., 1) in the radial direction, the first-stage planetary gears 324 drive the ring gear 332 in the opposite direction (e.g., the second clock direction D2) relative to the input shaft 310 and the first-stage sun gear 322 rotating in the first clock direction D1. As described above, the ring gear 332 is used as a power transmission element 133 to interface with the crankshaft 122 of the engine 120 to drive and facilitate engine starting. In fact, during the engine hot start mode, the power transfer assembly 132 is operated in a configuration of sun gear input and ring gear output, although it is operated with a relatively small gear ratio opposite to the mixed gear ratio of the first-stage planetary gears and the second-stage planetary gears 324, 346 compared to the cold engine start mode using the second-stage planetary gears 326.

[0086] In one example, the power transfer assembly 132 provides a 4:1 gear ratio in the power flow direction of the engine hot start mode. In other embodiments, other gear ratios (e.g., 3:1 to 7:1) may be provided. Taking into account the 4:1 gear ratio from the power transmission belt device 200, during the engine hot start mode, a final 16:1 gear ratio (e.g., about 12:1 to about 28:1) can be achieved for the starter-generator device 130 between the electric machine 134 and the engine 120. Thus, for example, if the electric machine 134 rotates at 10,000 RPM, the crankshaft 122 of the engine 120 rotates at about 600-700 RPM. In one example, the torque output of the power transfer assembly 132 for the engine 120 is about 400-600 Nm. Therefore, the electric machine 134 can therefore have a normal operating speed, which has a relatively low speed and a high torque output for engine starting or supercharging.

[0087] refer to Fig.12 , which is similar to the power transmission component 132 Figure 5 A partial cross-sectional view with arrows marking the direction of power flow. Fig.12 The power flow arrows of 130 specifically depict operation of the power transfer assembly 132 in the boost mode.

[0088] In this example, the actuator assembly 380, commanded by the controller 150, is used to pivot the cam plate 370 to the third angular position. In this position, the third cam tooth 378 of the cam plate 370 engages the second face 412 of the high-range clutch 410 to place the high-range clutch 410 in the engaged position. Also in the third angular position, the first cam tooth 376 of the cam plate 370 is received within the opening 397 of the low-range clutch 390, and the second cam tooth 377 of the cam plate 370 is received within the opening 407 of the mid-range clutch 400, thereby causing the low-range clutch 390 and the mid-range clutch 400 to remain in the disengaged position. As the third cam tooth 378 of the cam plate 370 engages the second face 412 of the high-range clutch 410, the high-range clutch 410 is pressed toward the gear set 320. When the high-range clutch 410 is urged in this direction, the clutch teeth 416 of the high-range clutch 410 extend through the third slots 426 in the static plate 420 and enter the third engagement element 434, resulting in the engaged position of the high-range clutch 410. As described above, the engagement of the third engagement element 434 by the high-range clutch 410 serves to lock the second-stage sun gear 340 to the first-stage sun gear 322. In the disengaged position, the clutch teeth 396 of the low-range clutch 390 and the clutch teeth 406 of the mid-range clutch 400 may be at least partially positioned within the slots 424, 425 of the static plate 420, although in some embodiments, the clutch teeth 396, 406 of the disengaged clutches 390, 400 may be completely retained outside of the static plate 420.

[0089] Since the second stage sun gear 340 and the first stage sun gear 322 are locked to rotate together, the power transmission assembly 132 can be operated in the boost mode. In the boost mode, the engine 120 can be initially started and the controller 150 energizes the electric machine 134 to operate as an electric motor. In particular and with additional reference to Figure 3, the electric machine 134 rotates the pulley 220 in the second clock direction D2, thereby driving the belt 230 and the pulley 210 in the second clock direction D2. The pulley 210 drives the element 135 in the second clock direction D2, thereby driving the input shaft 310. The rotation of the input shaft 310 drives the rotation of the first-stage sun gear 322, and the rotation of the first-stage sun gear 322 in turn drives the rotation of the second-stage sun gear 340, causing the first-stage sun gear 322, the second-stage sun gear 340, the first-stage planetary gear carrier 326, the first-stage planetary gears 324, the second-stage planetary gear carrier 348, and the second-stage planetary gears 346 to rotate as a unit with the input shaft 310 around the rotation axis 300 to drive the ring gear 332. Because the other components of the planetary gear set 320 rotate with the input shaft 310, the ring gear 332 is driven in the same second clock direction D2. As described above, the ring gear 332 serves as the power transmission element 133 to interface with the crankshaft 122 of the engine 120 to drive the engine 120. In practice, during the boost mode, the power transmission assembly 132 operates in a sun gear input, ring gear output configuration.

[0090] In one example, the power transfer assembly 132 provides a 1:1 gear ratio in the direction of power flow in the boost mode. In other embodiments, other gear ratios may be provided. Considering the 4:1 gear ratio from the power transmission belt device 200, during the boost mode, a final 4:1 gear ratio can be achieved for the starter-generator device 130 between the electric machine 134 and the engine 120. Thus, for example, if the electric machine 134 rotates at 10,000 RPM, the crankshaft 122 of the engine 120 rotates at approximately 2500 RPM. Therefore, the electric machine 134 can therefore have a normal operating speed while providing an appropriate boost speed to the engine 120.

[0091] refer to Fig.13 , which is similar to the power transmission component 132 Figure 5 A cross-sectional view with arrows marking the direction of power flow. Fig.13 The power flow arrows of 130 specifically depict operation of the power transfer assembly 132 in the power generation mode.

[0092] In this example, the function of the actuator assembly 380 commanded by the controller 150 is to pivot the cam plate 370 to the third angular position. As described above, in this position, the third cam teeth 378 of the cam plate 370 engage the second face 412 of the high-range clutch 410, so that the high-range clutch 410 is engaged and the low-range clutch 390 and the mid-range clutch 400 are disengaged. When the high-range clutch 410 is engaged, the clutch teeth 416 of the high-range clutch 410 extend through the third slot 426 in the static plate 420 and enter the third engagement element 434, and the third engagement element 434 is used to lock the second stage sun gear 340 to the first stage sun gear 322.

[0093] Since the second stage sun gear 340 and the first stage sun gear 322 are locked to rotate together, the power transfer assembly 132 can be operated in the power generation mode. After the engine starting mode and / or the boost mode, the engine 120 begins to accelerate to exceed the speed provided by the power transfer assembly 132, and the electric machine 134 is commanded to slow down and stop providing torque to the power transfer assembly 132. When the engine 120 has stabilized to a sufficient speed and the electric machine 134 has been sufficiently slowed down or stopped, as described above, the high gear clutch 410 is engaged to operate the power transfer assembly 132 in the power generation mode.

[0094] In the power generation mode, the engine 120 rotates the crankshaft 122 and the power transmission element 133 engaged with the ring gear 332, thereby driving the ring gear 332 in the second clock direction D2. The ring gear 332 drives the first stage planetary gears 324 and the second stage planetary gears 346, which drive the first stage sun gear 322 and the second stage sun gear 340 respectively.

[0095] Since the first-stage sun gear 322 is engaged with the second-stage sun gear 340, the rotation of the first-stage sun gear 322 and the second-stage sun gear 340 is transmitted to the input shaft 310. Therefore, as the ring gear 332 rotates in the second clock direction D2, the input shaft 310 is driven and rotates similarly in the second clock direction D2 at the same rotation rate. As described above, the input shaft 310 is connected to the electric machine 134 via the power transmission belt device 200 and provides output power to the electric machine 134 in the second clock direction D2. In fact, during the power generation mode, the power transmission assembly 132 operates in a configuration of a ring gear input and a sun gear output.

[0096] In one example, the power transfer assembly 132 provides a 1:1 gear ratio in the power flow direction of the generating mode. In other embodiments, other gear ratios may be provided. Considering the 4:1 gear ratio from the power transmission belt device 200, a 4:1 gear ratio may be achieved for the starter-generator device 130 between the electric machine 134 and the engine 120 during the generating mode. As a result, the electric machine 134 can therefore have normal operating speeds in both power flow directions and have a relatively low torque output during generating.

[0097] As will now be described, the power transfer assembly 132 may be further configured to facilitate transitions between modes, particularly by decelerating the electric machine 134. Referring now to Fig.15 , which is based on an example Figure 5 A closer and more detailed view of a portion of. Fig.15 The view in FIG. 1 specifically depicts a drag clutch or synchronized clutch 440. As shown, the drag clutch 440 is located between the input shaft 310 and the ring gear cover 333 mounted on the ring gear 332. In particular, the drag clutch 440 includes: a shaft plate 446, which is mounted on the input shaft 310 and rotates with the input shaft 310. The drag clutch 440 also includes one or more cover plates 444 parallel to each other, which are mounted on the ring gear cover 333. In this example, the shaft plate 446 is mounted between the above-mentioned cover plates 444. A spring (shown schematically) 448 can be provided to push the cover plate 444 and the shaft plate 446 together so that the plates 444, 446 have frictional engagement. This frictional engagement generates a drag force between the input shaft 310 and the ring gear 332 (and therefore between the electric machine 134 and the engine 120).

[0098] Because the electric machine 134 generally moves at a higher speed than the engine 120, the drag clutch 440 generally operates to reduce the speed of the electric machine 134 relative to the engine 120 to achieve synchronization. This facilitates transitions between modes, particularly between an engine cold start mode and an engine hot start mode, between an engine hot start mode and a boost mode, and between a boost mode and a generator mode.

[0099] The frictional engagement between the plates 444, 446 of the drag clutch 440 (particularly the force of the spring 448) can be preset or "preloaded" with a specified amount of force as needed or desired to provide an appropriate amount of drag force. Although other drag forces can be provided, an example drag force can be, for example, 10Nm. In one embodiment, the engagement of the clutch 390, 400, 410 with the gear set 320 can cause the gear set 320 to press against the drag clutch 440, thereby increasing the drag force to further reduce the electric motor speed and promote a faster transition.

[0100] Thus, various embodiments of a vehicle electrical system including an integrated starter-generator device have been described. Various transmission components may be included in the device, thereby reducing the space occupied by the system. The power transmission component can provide multiple speeds or gear ratios, as well as transitions between multiple speeds / multiple gear ratios. One or more clutch devices can be used to selectively apply torque to the gear set of the power transmission component in both power flow directions. Direct mechanical engagement with the engine shaft reduces complexity and improves system reliability. The use of a planetary gear set in the power transmission component can provide a high gear reduction and torque capacity within a compact space range and reduce backlash. Due to the bidirectional nature of the power transmission component, a power transmission belt device can be implemented using only a single belt tensioner, thereby providing a relatively compact and simple assembly. In addition, by using a power transmission belt device (in which a belt and a pulley are coupled together and transmit power between an electric machine and a power transmission component, rather than directly connecting and coupling the electric machine to the power transmission component), the electric machine can be mounted to be separated from the power transmission component, thereby better mounting the engine in the vehicle engine compartment. In addition, by connecting the electric machine to the power transmission component using a belt and a pulley, additional gear ratios (e.g., a 4:1 gear ratio) can be obtained. The embodiments discussed above include a dual planetary gear set, sun gear input, ring gear output configuration to provide an engine cold start mode and an engine hot start mode, and a ring gear input, sun gear output configuration to provide a generator mode. In this way, a four-mode assembly can be provided.

[0101] As described above, the dog clutch arrangement provides a degree of flexibility to the clutch to change the power flow path in a relatively compact and robust assembly. The cam arrangement cooperates with the dog clutch arrangement to reposition the clutch from a disengaged position to an engaged position based on angular position in a reliable and relatively simple manner. In some examples, the combined starter-generator clutch may further include a drag clutch that functions to facilitate synchronization during speed or direction changes.

[0102] In addition, the following examples are provided and are numbered for ease of reference.

[0103] 1. A combined starter-generator device for a working vehicle with an engine, the starter-generator device comprising: an electric machine; a gear set configured to receive rotational input from the electric machine and the engine and to couple the electric machine and the engine in a first power flow direction and a second power flow direction, the gear set configured to operate in one of a plurality of gear ratios in the first power flow direction and in at least one gear ratio in the second power flow direction; a clutch device having at least one acting clutch, the at least one acting clutch being selectively coupled to the gear set to achieve a gear ratio in the first power flow direction and the second power flow direction; wherein the clutch device further comprises at least one drag clutch to apply a drag force to the gear set to decelerate the electric machine.

[0104] 2. A combined starter-generator device according to Example 1, wherein the gear set includes an input shaft that receives rotational input from the electric machine along a first power flow direction, and wherein at least one drag clutch includes a first drag clutch portion mounted on the input shaft.

[0105] 3. A combined starter-generator device according to Example 2, wherein the gear set includes an output element that rotates with the engine, and wherein the at least one drag clutch includes a second drag clutch portion that is mounted to rotate with the output element.

[0106] 4. A combined starter-generator device according to Example 3, wherein the gear set includes a ring gear serving as an output element; and a ring gear cover mounted within the ring gear to at least partially surround the gear set and rotate with the ring gear, and a second drag clutch portion is mounted on the ring gear cover.

[0107] 5. The combined starter-generator device of Example 4, wherein the first drag clutch portion comprises: a flange mounted on the input shaft; and a shaft plate extending from the flange.

[0108] 6. A combined starter-generator device according to Example 5, wherein the second drag clutch portion includes at least one cover plate extending from the ring gear cover, and the shaft plate frictionally engages with the at least one cover plate to apply the drag force.

[0109] 7. A combined starter-generator arrangement according to Example 6, wherein the drag force is approximately 10 Nm.

[0110] 8. The combined starter-generator arrangement of example 7 wherein the at least one drag clutch is spring loaded to passively apply a drag force to the input shaft.

[0111] 9. The combined starter-generator device of Example 6, wherein:

[0112] wherein the gear set is configured to operate in at least one of a first gear ratio, a second gear ratio, and a third gear ratio in a first power flow direction, and in at least a fourth gear ratio in a second power flow direction, and wherein the at least one drag clutch is configured to decelerate the electric machine during a transition between the first gear ratio, the second gear ratio, and the third gear ratio, and during a transition between the first power flow direction and the second power flow direction.

[0113] 10. A combined starter-generator device according to Example 9, wherein the clutch device is a dog clutch device, which is selectively connected to the gear set to achieve a first gear ratio, a second gear ratio and a third gear ratio along a first power flow direction, and a fourth gear ratio along a second power flow direction, and wherein the combined starter-generator device also includes a cam plate, which is configured to convert the at least one acting clutch from a disengaged position in which the at least one acting clutch is disengaged from the gear set to an engaged position in which the at least one acting clutch is connected to the gear set.

[0114] 11. A combined starter-generator device according to Example 10, wherein the at least one acting clutch includes at least a first clutch, a second clutch and a third clutch, each of the first clutch, the second clutch and the third clutch being selectively repositioned between an engaged position and a disengaged position, and wherein the first clutch, the second clutch and the third clutch are annular, wherein when the first clutch and the second clutch are both in the disengaged position, the second clutch is concentrically arranged in the first clutch, and when the second clutch and the third clutch are both in the disengaged position, the third clutch is concentrically arranged in the second clutch; and the cam plate is generally a disc having a first face and a second face, and the cam plate includes a plurality of cam teeth extending from the first face to engage with the first clutch, the second clutch and the third clutch and convert the first clutch, the second clutch and the third clutch from the disengaged position to the engaged position.

[0115] 12. A combined starter-generator device according to Example 11, wherein the cam plate is configured to pivot within a range of angular positions, wherein, at the first angular position, at least one first cam tooth engages a first clutch, and the second clutch and the third clutch remain separated relative to at least one second cam tooth and at least one third cam tooth, and wherein, at the second angular position, the at least one second cam tooth engages a second clutch, and the first clutch and the third clutch remain separated relative to the at least one first cam tooth and the at least one third cam tooth, and wherein, at the third angular position, the at least one third cam tooth engages a third clutch, and the first clutch and the second clutch remain separated relative to the at least one first cam tooth and the at least one second cam tooth.

[0116] 13. A combined starter-generator device according to Example 12, wherein the at least one first cam tooth is radially and circumferentially offset relative to the at least one second cam tooth, and the at least one second cam tooth is radially and circumferentially offset relative to the at least one third cam tooth.

[0117] 14. A combined starter-generator device according to Example 13, wherein the first clutch includes a first ring base and at least one first clutch tooth extending from the first ring base, and the second clutch includes a second ring base and at least one second clutch tooth extending from the second ring base, and the third clutch includes a third ring base and at least one third clutch tooth extending from the third ring base; and wherein, in corresponding engagement positions of the first clutch, the second clutch and the third clutch, the at least one first clutch tooth, the at least one second clutch tooth and the at least one third clutch tooth are engaged with the gear set.

[0118] 15. A combined starter-generator device according to Example 14, wherein the gear set includes a compound planetary gear train, the compound planetary gear train including an input shaft, a first-stage sun gear and a second-stage sun gear, a first-stage planetary gear and a second-stage planetary gear, a first-stage planetary gear carrier and a second-stage planetary gear carrier, and a ring gear, wherein the first-stage planetary gear carrier is connected to the second-stage sun gear by means of a spline, wherein the number of teeth of the first-stage planetary gear is different from the number of teeth of the second-stage planetary gear; wherein, in an engine cold start mode, the first clutch is in an engaged position to ground the second-stage planetary gear carrier, and the second clutch and the third clutch are in a split position. The first clutch and the third clutch are in a disengaged position, and the rotational power from the electric machine moves from the input shaft to the first-stage sun gear, the first-stage planetary gears, the first-stage planetary gear carrier, the second-stage sun gear, the second-stage planetary gears and the ring gear along the first power flow direction, thereby being output to the engine at a first gear ratio; and wherein, in the engine hot start mode, the second clutch is in an engaged position to ground the second-stage sun gear, the first clutch and the third clutch are in a disengaged position, and the rotational power from the electric machine moves from the input shaft to the first-stage sun gear, the first-stage planetary gears and the ring gear along the first power flow direction, thereby being output to the engine at a second gear ratio.

[0119] As will be appreciated by those skilled in the art, certain aspects of the subject matter of the present disclosure may be described as methods, systems (e.g., a work vehicle control system included in a work vehicle), or computer program products. Thus, particular embodiments may be implemented in their entirety as hardware, software (including firmware, resident software, microcode, etc.), or as a combination of software and hardware aspects. Furthermore, particular embodiments may take the form of a computer program product on a computer-usable storage medium having computer-usable program code embedded in the medium.

[0120] Any suitable computer-usable or computer-readable medium may be used. A computer-usable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-usable or computer-readable storage medium (including a storage device associated with a computing device or a client electronic device) may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared or semiconductor system, device or device, or any suitable combination of the foregoing systems, devices or devices. More specific examples of computer-readable media (a non-exclusive list) may include: an electrical connector having one or more metal wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), light, a portable read-only compact disk storage (CD-ROM), an optical storage device. In the context of this document, a computer-usable or computer-readable storage medium may be any tangible medium that is capable of containing or storing a program used by or associated with an instruction execution system, device or device.

[0121] Computer readable signal media may include a propagated data signal having a computer readable program code embedded therein, the program code being, for example, in baseband or as part of a carrier wave. Such propagated signals may take a variety of forms, including but not limited to electromagnetic, optical, or any suitable combination thereof. Computer readable signal media may be non-volatile and may be any computer readable medium that is not a computer readable storage medium and is capable of transmitting, propagating, or transporting a program used by or associated with an instruction execution system, device, or apparatus.

[0122] This article describes aspects of certain embodiments with reference to flowcharts and / or method block diagrams, devices (systems) and computer program products according to embodiments of the present invention. It should be understood that the individual blocks of any flowchart and / or block diagram, and the combination of multiple blocks of the flowchart and / or block diagram can be executed by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a processor of a special-purpose computer, or a processor of other programmable data processing devices to obtain a machine so that instructions executed via processing of a computer or other programmable data processing device create a device for performing the functions / behaviors specified in the blocks or multiple blocks of the flowchart and / or block diagram.

[0123] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to function in a specific manner, such that the instructions stored in the computer-readable memory generate a manufacturing specification that includes executing the functions / behaviors specified in a block or blocks in a flowchart and / or block diagram.

[0124] Computer program instructions may also be loaded into a computer or other programmable data processing device to form a series of operational steps to be performed on the computer or other programmable device to generate a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for performing the functions / behaviors specified in a block or blocks of a flowchart and / or block diagram.

[0125] The flowcharts and block diagrams in the accompanying drawings illustrate the operation of possible embodiments of algorithms, functions, systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, a section, or a portion of a code, which includes one or more executable instructions for performing a specific logical function. In addition, in some alternative embodiments, the functions mentioned in multiple blocks (or functions described in other ways herein) may occur in an order other than the order mentioned in the accompanying drawings. For example, two blocks shown in succession (or two boxes described in succession) may in fact be substantially executed simultaneously, or multiple blocks (or operations) may sometimes be executed in reverse order depending on the functions involved. It should also be noted that each block of a block diagram and / or a flowchart, a combination of multiple blocks in a block diagram and / or a flowchart, can be executed by a special-purpose hardware-based system that performs a specific function or behavior, or a combination of special-purpose hardware and computer instructions.

[0126] The terms used in this article are only for describing specific embodiments and are not intended to limit the present disclosure. As used in this article, the singular forms "a", "an", and "the" are also intended to include plural forms unless the context clearly dictates. It should also be understood that the use of the terms "include" and / or "comprise" in the specification indicates the presence of the listed features, wholes, steps, operations, elements and / or parts, but does not exclude the presence or addition of one or more of other features, wholes, steps, operations, elements, parts, and / or combinations thereof.

[0127] The specification of the present disclosure has been shown for the purpose of illustration and description, but it is not intended to be exclusive or to limit the present disclosure to the disclosed content. For those skilled in the art, many modifications and changes are obvious without separating the scope and spirit of the present disclosure. The embodiments explicitly referenced herein are selected and described in order to best explain the principles of the present disclosure and their practical application, and to enable other ordinary technicians in the field to understand the present disclosure and recognize various alternative embodiments, modifications and changes of the described examples. Therefore, various embodiments and implementations other than those explicitly described are within the scope of the following claims.

Claims

1. A combined starter-generator device for a working vehicle having an engine, the starter-generator device include: Electric machines; a gear set configured to receive rotational input from the electric machine and the engine and to couple the electric machine and the engine in a first power flow direction and a second power flow direction, the gear set configured to operate in one of a plurality of gear ratios in the first power flow direction and in at least one gear ratio in the second power flow direction; a clutch arrangement having at least one active clutch selectively coupled to the gear set to achieve a gear ratio in a first power flow direction and a second power flow direction; The clutch device further comprises at least one drag clutch for applying a drag force to the gear set to decelerate the electric machine.

2. The combined starter-generator device according to claim 1, in, The gear set includes an input shaft that receives a rotational input from the electric machine in a first power flow direction, and wherein the at least one drag clutch includes a first drag clutch portion mounted on the input shaft.

3. The combined starter-generator device according to claim 2, in, The gear set includes an output member that rotates with the engine, and Therein, the at least one drag clutch includes a second drag clutch part mounted for rotation with the output member.

4. The combined starter-generator device according to claim 3, in, The gear set includes a ring gear as an output element; and a ring gear cover mounted within the ring gear to at least partially surround the gear set and rotate together with the ring gear, the second drag clutch portion being mounted on the ring gear cover.

5. The combined starter-generator device according to claim 4, in, The first drag clutch part includes a flange mounted on the input shaft and a shaft plate extending from the flange.

6. The combined starter-generator device according to claim 5, in, The second drag clutch portion includes at least one cover plate extending from a ring gear cover, and the shaft plate frictionally engages the at least one cover plate to apply a drag force.

7. The combined starter-generator device according to claim 6, in, The drag force is 10 Nm.

8. The combined starter-generator device according to claim 7, in, The at least one drag clutch is spring loaded to passively apply a drag force to the input shaft.

9. The combined starter-generator device according to claim 6, wherein: in, The gear set is configured to operate in at least one of a first gear ratio, a second gear ratio, and a third gear ratio in a first power flow direction and in at least a fourth gear ratio in a second power flow direction, and Wherein the at least one drag clutch is configured to decelerate the electric machine during transitions between a first gear ratio, a second gear ratio, and a third gear ratio and during transitions between a first power flow direction and a second power flow direction.

10. The combined starter-generator arrangement according to claim 9, in, the clutch device is a dog clutch device selectively coupled to the gear set to achieve a first gear ratio, a second gear ratio, and a third gear ratio in a first power flow direction and a fourth gear ratio in a second power flow direction, and The combined starter-generator device further comprises a cam plate configured to convert the at least one acting clutch from a disengaged position in which the at least one acting clutch is disengaged from the gear set to an engaged position in which the at least one acting clutch is connected to the gear set.

11. The combined starter-generator device according to claim 10, in, The at least one active clutch includes at least a first clutch, a second clutch, and a third clutch, each of the first clutch, the second clutch, and the third clutch being selectively repositionable between an engaged position and a disengaged position, and wherein the first clutch, the second clutch and the third clutch are annular, wherein when the first clutch and the second clutch are both in the disengaged position, the second clutch is concentrically arranged within the first clutch, and when the second clutch and the third clutch are both in the disengaged position, the third clutch is concentrically arranged within the second clutch; and The cam plate is in a disc shape having a first face and a second face, and includes a plurality of cam teeth extending from the first face to engage with and convert the first, second, and third clutches from a disengaged position to an engaged position.

12. The combined starter-generator arrangement according to claim 11, in, The cam plate is configured to pivot within a range of angular positions. wherein, at a first angular position, at least one first cam tooth engages the first clutch and the second clutch and the third clutch remain disengaged relative to the at least one second cam tooth and the at least one third cam tooth, and wherein, at a second angular position, the at least one second cam tooth engages the second clutch and the first clutch and the third clutch remain disengaged relative to the at least one first cam tooth and the at least one third cam tooth, and Wherein, in the third position, the at least one third cam tooth engages the third clutch, and the first clutch and the second clutch remain disengaged relative to the at least one first cam tooth and the at least one second cam tooth.

13. The combined starter-generator arrangement according to claim 12, in, The at least one first cam tooth is radially and circumferentially offset relative to the at least one second cam tooth, and The at least one second cam tooth is radially and circumferentially offset relative to the at least one third cam tooth.

14. The combined starter-generator arrangement according to claim 13, in, The first clutch comprises a first ring base and at least one first clutch tooth extending from the first ring base, and the second clutch comprises a second ring base and at least one second clutch tooth extending from the second ring base, and the third clutch comprises a third ring base and at least one third clutch tooth extending from the third ring base; and Wherein, in the respective engagement positions of the first clutch, the second clutch and the third clutch, the at least one first clutch tooth, the at least one second clutch tooth and the at least one third clutch tooth are engaged with the gear set.

15. The combined starter-generator arrangement according to claim 14, in, The gear set includes a compound planetary gear train including an input shaft, a first-stage sun gear and a second-stage sun gear, first-stage planetary gears and second-stage planetary gears, a first-stage planetary gear carrier and a second-stage planetary gear carrier, and a ring gear, wherein the first-stage planetary gear carrier is connected to the second-stage sun gear by means of a spline, wherein the number of teeth of the first-stage planetary gears is different from the number of teeth of the second-stage planetary gears; wherein, in an engine cold start mode, the first clutch is in an engaged position to fix the second-stage planetary gear carrier, the second clutch and the third clutch are in a disengaged position, and the rotational power from the electric machine moves from the input shaft to the first-stage sun gear, the first-stage planetary gear, the first-stage planetary gear carrier, the second-stage sun gear, the second-stage planetary gear and the ring gear along a first power flow direction, thereby being output to the engine at a first gear ratio; and In which, in the engine hot start mode, the second clutch is in the engaged position to fix the second-stage sun gear, the first clutch and the third clutch are in the disengaged position, and the rotational power from the electric machine moves from the input shaft to the first-stage sun gear, the first-stage planetary gears and the ring gear along the first power flow direction, thereby being output to the engine at a second gear ratio.

16. The combined starter-generator arrangement according to claim 15, in, In the boost mode, the third clutch is in an engaged position to couple the second-stage sun gear to the first-stage sun gear, and the first clutch and the second clutch are in a disengaged position, and the rotational power from the electric machine is moved from the input shaft to the first-stage sun gear and the second-stage sun gear, the first-stage planetary gear and the second-stage planetary gear, and the ring gear in a first power flow direction to be output to the engine at a third gear ratio; and In which, in the power generation mode, the third clutch is in the engaged position to connect the second-stage sun gear to the first-stage sun gear, and the first clutch and the second clutch are in the disengaged position, and further, the rotational power from the engine moves from the ring gear to the first-stage planetary gears and the second-stage planetary gears, the first-stage sun gear and the second-stage sun gear and the input shaft along the second power flow direction, thereby being output to the electric machine at a fourth gear ratio.

17. The combined starter-generator arrangement according to claim 16, in, The third gear ratio and the fourth gear ratio are both 1:1 in the gear set; and The first transmission ratio is greater than the second transmission ratio, and the second transmission ratio is greater than the third transmission ratio.

18. A transmission system assembly for a work vehicle, include: engine; Electric machines; a gear set configured to receive rotational input from the electric machine and the engine and to couple the electric machine and the engine in a first power flow direction and a second power flow direction, the gear set configured to operate in at least one of a first gear ratio, a second gear ratio, and a third gear ratio in the first power flow direction and in at least the third gear ratio in the second power flow direction; and a clutch device having at least one active clutch selectively coupled to the gear set to achieve a first gear ratio, a second gear ratio, and a third gear ratio in a first power flow direction and to achieve a third gear ratio in a second power flow direction, wherein the clutch device further comprises at least one drag clutch to apply a drag force to the gear set to decelerate the electric machine; and A cam plate is configured to transition the at least one active clutch from a disengaged position in which the at least one active clutch is disengaged from the gear set to an engaged position in which the at least one active clutch is coupled to the gear set.

19. The transmission system assembly according to claim 18, in, The gear set includes an input shaft that receives a rotational input from an electric machine in a first power flow direction, and an output element that rotates with the engine, and Therein, at least one drag clutch includes: a first portion mounted on the input shaft; and a second portion mounted to rotate with the output member, wherein the first portion and the second portion frictionally engage each other to apply a drag force.

20. The transmission system assembly according to claim 19, in, The drag force is 10 Nm.

Images