Vehicle drive device

Abstract

Disclosed is a vehicle drive device. In a case where a reaction force is applied to a differential device by using the power generation torque of a TF rotary machine (MGF) for power distribution, the energy efficiency of the vehicle drive device as a whole is improved. In a torque split mode in which power generation control of the MGF torque (TDmgf) is performed in such a way that the torque distribution ratio (Rx) becomes the target distribution ratio (Rdis) and the total torque (Tpu1) of the first power source (PU1) is controlled in such a way that the required drive torque (Trdem) is obtained regardless of the MGF torque (TDmgf) during distribution, when it is possible to drive the TM rotary machine (MGM) by using part or all of the power generation power (WDgmgf) during distribution obtained by the power generation control and bring the operating point of the engine closer to the fuel economy optimal line (Lfl) (the determination in step S5 is "Yes"), part or all of the power generation power (WDgmgf) during distribution is supplied to the TM rotary machine (MGM) without passing through the battery to drive the TM rotary machine (MGM).

Description

Technical Field

[0001] The present invention relates to a drive device for a vehicle, and particularly to a technique for improving the energy efficiency of a drive device for a vehicle having a power distribution device that distributes a part of the power input to a first output shaft from a power source to a second output shaft. Background Art

[0002] A known drive device for a vehicle includes: (a) a power source having an engine and a first rotary electric machine; (b) a first output shaft that inputs power from the power source and outputs the power to one of the front wheels and the rear wheels; (c) a second output shaft that outputs power to the other of the front wheels and the rear wheels; (d) a power distribution device that distributes a part of the power from the power source input to the first output shaft to the second output shaft; and (e) a control device. The device described in Patent Document 1 is an example thereof, and describes the following: As the above power distribution device, it includes: (d-1) a second rotary electric machine; and (d-2) a differential device having a first rotary element to which the second rotary electric machine is connected, a second rotary element to which the first output shaft is connected, and a third rotary element to which the second output shaft is connected, (d-3) a part of the power input from the power source to the first output shaft is distributed to the second output shaft by applying a reaction force to the first rotary element by using the torque of the second rotary electric machine.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2007-246056 Summary of the Invention

[0006] However, generally, when generating a power generation torque (also referred to as a regeneration torque) of the second rotary electric machine of the above power distribution device to control the reaction force of the first rotary element, the generated power obtained by the power generation control of the second rotary electric machine is charged to a power storage device, taken out from the power storage device according to the driving conditions, and used for torque control of the first rotary electric machine and the like. However, when power is transferred via the power storage device in this way, power loss occurs during charging and discharging, so there is room for improvement in terms of improving the overall energy efficiency of the device.

[0007] The present invention has been completed based on the above circumstances, and an object thereof is to improve the overall energy efficiency of a drive device for a vehicle in the case of performing power distribution by applying a reaction force to a differential device by using the power generation torque of a second rotary electric machine.

[0008] To achieve this object, the first invention provides a vehicle drive device having: a power source having an engine and a first rotating electric machine; a first output shaft that inputs power from the power source and outputs the power to one of a front wheel and a rear wheel; a second output shaft that outputs power to the other of the front wheel and the rear wheel; a power distribution device that distributes a part of the power from the power source input to the first output shaft to the second output shaft; and a control device. The vehicle drive device is characterized in that: (a) the power distribution device includes (a-1) a second rotating electric machine and (a-2) a differential device having a first rotating element to which the second rotating electric machine is connected, a second rotating element to which the first output shaft is connected, and a third rotating element to which the second output shaft is connected, and (a-3) the power distribution device is configured to distribute a part of the power input to the first output shaft from the power source to the second output shaft by applying a reaction force to the first rotating element by using the power generation torque of the second rotating electric machine; (b) the control device includes a torque separation control unit that performs power generation control to control the power generation torque of the second rotating electric machine so that the power distribution ratio for the first output shaft and the second output shaft becomes a target distribution ratio, and controls the total torque of the power source including the engine and the first rotating electric machine so as to obtain a required drive torque regardless of the power generation torque; (c) the torque separation control unit has a power consumption control unit that supplies a part or all of the power generation power obtained by the power generation control to the first rotating electric machine without passing through a power storage device to drive the first rotating electric machine in such a manner that the operating state of the engine approaches the optimal state of fuel economy.

[0009] In the vehicle drive device according to the first invention, the second invention is characterized in that the torque separation control unit includes a charging control unit that charges all of the power generation power into the power storage device, and selects whether to perform control based on the charging control unit or control based on the power consumption control unit according to the operating state of the engine.

[0010] In the vehicle drive device according to the second invention, the third invention is characterized in that the torque separation control unit determines whether the operating state of the engine can be made to approach the optimal state of fuel economy by supplying a part or all of the power generation power to the first rotating electric machine to drive the first rotating electric machine. If it is possible to approach the optimal state of fuel economy, control based on the power consumption control unit is selected; if it is not possible to approach the optimal state of fuel economy, control based on the charging control unit is selected.

[0011] In the vehicle drive device of the second invention or the third invention, the torque separation control unit determines whether the charge state value of the power storage device exceeds a predetermined determination value. When the value exceeds the determination value, the selection based on the operating state of the engine is not performed, and all of the generated power is supplied to the first rotating electric machine without passing through the power storage device to drive the first rotating electric machine.

[0012] In the vehicle drive device of any one of the first invention to the fourth invention, the power consumption control unit, when it is possible to drive the first rotating electric machine by supplying the generated power to the first rotating electric machine and bring the operating state of the engine close to the optimal state of fuel economy, and when a part of the generated power remains, charges the remaining power to the power storage device.

[0013] In such a vehicle drive device, there is a power consumption control unit in the torque separation control unit that controls the generated torque of the second rotating electric machine so that the power distribution ratio becomes the target distribution ratio and controls the total torque of the power source so as to obtain the required drive torque regardless of the generated torque. The power consumption control unit drives the first rotating electric machine by supplying part or all of the generated power obtained by the power generation control to the first rotating electric machine without passing through the power storage device in such a way that the operating state of the engine is close to the optimal state of fuel economy. Therefore, compared with the case where the generated power obtained by the power generation control is always charged to the power storage device, the power loss caused by the charge and discharge of the power storage device is reduced, and the energy efficiency of the entire device is improved. In addition, the fuel economy of the engine is improved by using the generated power to drive the first rotating electric machine in such a way that the operating state of the engine is close to the optimal state of fuel economy, which also contributes to the improvement of the energy efficiency of the entire device.

[0014] In the case of the second invention having a charge control unit that charges all of the generated power obtained by the power generation control to the power storage device, the control based on the charge control unit or the control based on the power consumption control unit is selected according to the operating state of the engine. Therefore, the control based on the power consumption control unit can be appropriately executed according to the operating state of the engine, and the energy efficiency of the entire device can be improved by the execution of the control by the power consumption control unit.

[0015] In the third invention, it is determined whether part or all of the generated power obtained by power generation control can be supplied to the first rotating electric machine to drive the first rotating electric machine, so as to make the operating state of the engine approach the optimal state of fuel economy. When it is possible to approach the optimal state of fuel economy, the control based on the power consumption control unit is selected. Therefore, the control based on the power consumption control unit is appropriately executed according to the operating state of the engine, and the control can be executed by the power consumption control unit to improve the overall energy efficiency of the device.

[0016] In the fourth invention, when the state-of-charge value of the power storage device exceeds a predetermined determination value, the selection based on the operating state of the engine is not performed, and all the generated power obtained by power generation control is supplied to the first rotating electric machine to drive the first rotating electric machine without passing through the power storage device. Therefore, the power loss caused by the charge and discharge and full charge of the power storage device is suppressed.

[0017] In the fifth invention, when it is possible to make the operating state of the engine approach the optimal state of fuel economy by supplying the generated power obtained by power generation control to the first rotating electric machine to drive the first rotating electric machine, and when part of the generated power remains, the remaining power is charged to the power storage device. Therefore, the operating state of the engine can be reliably made to approach the optimal state of fuel economy, and the overall energy efficiency of the device can be appropriately improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a diagram for explaining the schematic structure of a vehicle drive device to which the present invention is applied, and is also a diagram for explaining the control functions and the main parts of a control system for various controls in the vehicle drive device.

[0019] Figure 2 It is for explaining Figure 1 the schematic structure of a hybrid transmission (HV T / M).

[0020] Figure 3 It is for explaining Figure 2 the working engagement table showing the relationship between the multiple AT gears of an automatic transmission and the combination of the operations of the engagement devices used in the AT gears.

[0021] Figure 4 It is for explaining Figure 1 the schematic structure of a transfer case (T / F).

[0022] Figure 5 It shows Figure 4 a collinear diagram showing the relative relationship of the rotational speeds of the respective rotating elements in the transfer case.

[0023] Figure 6 It is for explaining in Figure 4A working engagement table showing the relationship between each driving mode established in the transfer case and the control states of the respective engagement devices in the transfer case.

[0024] Figure 7 is Figure 6 A collinear diagram in the "H4_Torque Separation" mode, which is a diagram illustrating the torque applied to each part of the transfer case.

[0025] Figure 8 A diagram showing an example of the AT gear shift map used in the shift control of the automatic transmission and the driving mode shift map used in the shift control of the driving mode, and also a diagram showing their respective relationships.

[0026] Figure 9 is an illustration of Figure 1 A flowchart of the operation performed by the torque separation control section of the electronic control unit.

[0027] Figure 10 is an illustration of Figure 9 A diagram showing the method of determining whether the TM rotary machine MGM can be driven using the MGM torque based on the operating point of the engine in step S5.

[0028] Symbol Explanation

[0029] 10: Vehicle drive device; 12: Engine; 14: Front wheels; 16: Rear wheels; 24: Battery (power storage device); 28: Transfer case (power distribution device); 64: Differential device; 66: First output shaft; 72: Second output shaft; 130: Electronic control unit (control device); 142: Torque separation control section; 144: Power consumption control section; 146: Charge control section; S: Sun gear (first rotating element); CA: Gear carrier (second rotating element); R: Ring gear (third rotating element); MGM: TM rotary machine (first rotating electric machine); MGF: TF rotary machine (second rotating electric machine); PU1: First power source (power source); Tmgf: MGF torque (generating torque); SOC: Charge state value; α: Determination value; A: Operating point (operating state); Lfl: Fuel economy optimal line (fuel economy optimal state). Detailed Description of the Invention

[0030] The object of the present invention is a hybrid front and rear wheel drive vehicle, which has at least an engine and a first rotating electric machine as power sources, and a power distribution device having a second rotating electric machine and a differential device. The engine is an internal combustion engine such as a gasoline engine or a diesel engine. The first rotating electric machine and the second rotating electric machine are preferably motor generators capable of being selectively used as an electric motor and a generator, but in the case of traveling only in a torque split mode, the first rotating electric machine may also be an electric motor, and the second rotating electric machine may also be a generator.

[0031] The operating state of the engine can be evaluated, for example, by an operating point determined based on the engine speed and the engine torque. In this case, taking the engine speed and the engine torque as variables, a fuel economy optimal fuel economy best line is obtained in advance, so that the state where the operating point is located on the fuel economy best line can be judged as the best fuel economy state. The engine speed is determined by the vehicle speed and the gear ratio of the power transmission path. Therefore, when the operating point of the engine torque where the engine speed and the required driving torque can be obtained is a torque higher than the fuel economy best line, the first rotating electric machine is driven by the generated power obtained through the power generation control, so that the engine torque can be reduced by the torque amount of the first rotating electric machine and approach the fuel economy best line, and the control by the power consumption control unit can be executed. When the operating point of the engine is the same as or lower than the fuel economy best line, when the first rotating electric machine is driven by the generated power obtained through the power generation control, the engine torque is reduced by the torque amount of the first rotating electric machine and separated from the fuel economy best line, so that the control by the power consumption control unit cannot be performed. The operating state of the engine can also be evaluated using the throttle valve opening degree, the intake air amount, the fuel injection amount, etc. of the engine.

[0032] The power distribution device is configured, for example, such that in a state where the second output shaft is disconnected from the power source, a reaction force is applied to the first rotating element by the generated torque of the second rotating electric machine, so that a part of the power input from the power source to the first output shaft is distributed to the second output shaft, and only the distributed power is used to rotationally drive the second output shaft. The power distribution device may also be, as described in Patent Document 1, a center differential (center differential 10 in Patent Document 1) provided at the front stage of the power distribution device (motor torque addition mechanism 20 in Patent Document 1) to pre-distribute the power from the power source to both the first output shaft and the second output shaft, and adjust the power distribution ratio to be the target distribution ratio.

[0033] The differential device constituting the power distribution device is, for example, a single pinion type planetary gear device. The carrier of the planetary gear device is used as the second rotating element connected to the first output shaft, and one of the sun gear and the ring gear of the planetary gear device and the other are used as the first rotating element and the third rotating element. As the differential device, a double pinion type planetary gear device can also be used. In this case, the ring gear is used as the second rotating element connected to the first output shaft, and one of the sun gear and the carrier and the other are used as the first rotating element and the third rotating element. A power distribution device can also be constituted by using a plurality of planetary gear devices.

[0034] The power distribution device has, for example: (a) a TF clutch that connects any two of the first rotating element, the second rotating element, and the third rotating element to integrally rotate the differential device; (b) a TF brake that blocks the rotation of the third rotating element; (c) a first on-off device disposed between the TF input shaft that transmits the power of the power source, the first output shaft, and the first rotating element, and capable of switching between a first on-off state of cutting off the power transmission between the first rotating element and connecting the TF input shaft to the first output shaft and a second on-off state of cutting off the power transmission between the first output shaft and connecting the TF input shaft to the first rotating element; and (d) a second on-off device disposed between the third rotating element, the first output shaft, and the second output shaft, and capable of switching between a first on-off state of cutting off all power transmissions among the third rotating element, the first output shaft, and the second output shaft, a second on-off state of cutting off the power transmission between the first output shaft and connecting the third rotating element to the second output shaft, and a third on-off state of cutting off the power transmission between the third rotating element and connecting the first output shaft to the second output shaft. (e) The power distribution device is configured such that both the TF clutch and the TF brake are set to a non-operating state (released state), the first on-off device is set to the first on-off state, and the second on-off device is set to the second on-off state, so that a reaction force is applied to the first rotating element by the power generation torque of the second rotating motor, and thus a part of the power input from the power source to the first output shaft is distributed to the second output shaft via the third rotating element, forming a torque split mode of traveling by both the front wheels and the rear wheels. The power distribution device can form a torque split mode only by using the second rotating motor and the differential device, and can also omit part or all of the above TF clutch, TF brake, first on-off device, and second on-off device, and additionally set on-off devices such as clutches, and can adopt various methods.

[0035]

Embodiment

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in the following embodiments, the drawings are appropriately simplified or deformed, and the dimensional ratios, shapes, etc. of each part are not necessarily accurately depicted.

[0037] Figure 1 It is a diagram showing a schematic structure of a vehicle drive device 10 provided in a vehicle 8 to which the present invention is applied, and is a diagram showing the control functions of various controls for the vehicle drive device 10 and the main parts of the control system. In Figure 1 the vehicle drive device 10 includes an engine 12 (referred to as "ENG" in the figure) that functions as a power source, a TM rotary machine MGM, and a TF rotary machine MGF. The vehicle 8 is a hybrid vehicle. In addition, the vehicle drive device 10 includes a pair of left and right front wheels 14, a pair of left and right rear wheels 16, and a power transmission device 18. The power transmission device 18 is a vehicle power transmission device that transmits power from the engine 12 and the like to the front wheels 14 and the rear wheels 16, respectively. The engine 12, the TM rotary machine MGM, and the TF rotary machine MGF are used as power sources for the running of the vehicle 8. In particular, the engine 12 and the TM rotary machine MGM that output power to a torque converter 48 and an automatic transmission 50 described later are the first power source PU1. The TM rotary machine MGM included in the first power source PU1 is the first rotary electric machine. In addition, the TF rotary machine MGF included in a transfer 28 described later is the second rotary electric machine, and is the second power source PU2 that is used as a power source instead of the first power source PU1 or the second power source PU2 that is used as a power source in addition to the first power source PU1.

[0038] The vehicle 8 is an all-wheel drive vehicle, i.e., a front and rear wheel drive vehicle, that can distribute a part of the torque transmitted to the rear wheels 16 by the vehicle drive device 10 to the front wheels 14. The vehicle drive device 10 can also perform rear-wheel drive that transmits torque only to the rear wheels 16. Since the vehicle 8 has two front wheels 14 and two rear wheels 16 and has four wheels, it is also a four-wheel drive vehicle. In this embodiment, all-wheel drive (= AWD) and four-wheel drive (= 4WD) have the same meaning. In addition, rear-wheel drive is two-wheel drive (= 2WD).

[0039] The engine 12 is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine 12 controls the engine torque Te, which is the output torque of the engine 12, by controlling an engine control device 20 including a throttle actuator, a fuel injection device, an ignition device, etc. provided in the vehicle drive device 10 by an electronic control device 130 described later.

[0040] The rotary machine MGM for TM and the rotary machine MGF for TF are rotary electrical machines that have the function of an electric motor, which is an engine that generates mechanical power from electricity, and the function of a generator that generates electricity from mechanical power, and are so-called motor generators. The rotary machine MGM for TM and the rotary machine MGF for TF are respectively connected to the storage battery 24 provided in the vehicle drive device 10 via the inverter 22 provided in the vehicle drive device 10. The rotary machine MGM for TM and the rotary machine MGF for TF respectively control the MGM torque Tmgm, which is the torque of the rotary machine MGM for TM, and the MGF torque Tmgf, which is the torque of the rotary machine MGF for TF, by controlling the inverter 22 by an electronic control device 130 described later. The MGM torque Tmgm and the MGF torque Tmgf include, in addition to the power running torque that functions as an electric motor, the case of including the power generation torque (also called the regeneration torque) that functions as a generator. The storage battery 24 is a power storage device that supplies and receives power to and from each of the rotary machine MGM for TM and the rotary machine MGF for TF. The said power has the same meaning as electric energy without special distinction. The said power can be replaced with driving force, torque, power, etc. without special distinction.

[0041] The power transmission device 18 includes a hybrid transmission 26 (referred to as "HV T / M" in the figure), a transfer case 28 as a power distribution device (referred to as "T / F" in the figure), a front propeller shaft 30, a rear propeller shaft 32, a front differential (referred to as "FDiff" in the figure) 34, a rear differential (referred to as "RDiff" in the figure) 36, a pair of left and right front drive shafts 38, and a pair of left and right rear drive shafts 40. In the power transmission device 18, the power transmitted from the first power source PU1 to the transfer case 28 via the hybrid transmission 26 is further transmitted from the transfer case 28 to the rear wheels 16 via the rear propeller shaft 32, the rear differential 36, the rear drive shafts 40, etc. In addition, in the power transmission device 18, a part of the power transmitted from the first power source PU1 to the transfer case 28 is distributed by the transfer case 28 to the front wheel 14 side, and the distributed power is transmitted to the front wheel 14 via the front propeller shaft 30, the front differential 34, the front drive shafts 38, etc.

[0042] The hybrid transmission 26 includes a transmission case 42 as a non-rotating member. The transfer case 28 includes a transfer case 44 as a non-rotating member connected to the transmission case 42. The rotary machine MGM for TM is provided inside the transmission case 42. The rotary machine MGF for TF is provided inside the transfer case 44.

[0043] Figure 2 It is a diagram for explaining the schematic structure of the hybrid transmission 26. In Figure 2In this case, the transmission 26 for hybrid use includes a rotary machine connecting shaft 46, a torque converter 48, an automatic transmission 50, etc., which are disposed on a common rotation axis CL1 within the transmission case 42. The torque converter 48 and the automatic transmission 50 are configured to be substantially symmetric with respect to the rotation axis CL1. In Figure 2 the lower half is omitted with respect to the rotation axis CL1. The rotation axis CL1 is the axis of the crankshaft of the engine 12, the rotary machine connecting shaft 46 connected to the crankshaft, the transmission input shaft 52 as the input rotary member of the automatic transmission 50, the transmission output shaft 54 as the output rotary member of the automatic transmission 50, etc.

[0044] The rotary machine connecting shaft 46 is a rotary shaft that connects the engine 12 and the torque converter 48. An engine on / off clutch K0 is provided between the engine 12 and the rotary machine connecting shaft 46. The engine on / off clutch K0 is a clutch that cuts off the connection between the engine 12 and the rotary machine connecting shaft 46. The TM rotary machine MGM is disposed concentrically with the rotation axis CL1 within the transmission case 42 and is connected to the rotary machine connecting shaft 46 in a power-transmittable manner via a rotary machine on / off clutch K2. The rotary machine on / off clutch K2 is a clutch that cuts off the connection between the rotary machine connecting shaft 46 and the TM rotary machine MGM. The torque converter 48 includes a pump impeller 48a connected to the rotary machine connecting shaft 46 and a turbine impeller 48b connected to the transmission input shaft 52. The pump impeller 48a is the input member of the torque converter 48, and the turbine impeller 48b is the output member of the torque converter 48. The rotary machine connecting shaft 46 is also the input rotary member of the torque converter 48. The transmission input shaft 52 is also the output rotary member of the torque converter 48 that is integrally formed with the turbine shaft driven to rotate by the turbine impeller 48b. The torque converter 48 is a fluid transmission device that transmits the power from the first power source PU1 to the transmission input shaft 52 via a fluid. The torque converter 48 includes a lock-up clutch LU that connects the pump impeller 48a and the turbine impeller 48b. The lock-up clutch LU is a direct connection clutch that connects the input and output rotary members of the torque converter 48.

[0045] The automatic transmission 50 is in the power transmission path between the torque converter 48 and the transfer case 28. The transmission output shaft 54 is connected to the transfer case 28. The automatic transmission 50 is a mechanical transmission device that transmits the power from the first power source PU1 to the transfer case 28. In this way, the torque converter 48 and the automatic transmission 50 transmit the power from the first power source PU1 to the transfer case 28.

[0046] The automatic transmission 50 is, for example, a known planetary gear type automatic transmission having a multi-group planetary gear device including a first planetary gear device 56 and a second planetary gear device 58, and a plurality of engaging devices including a clutch C1, a clutch C2, a brake B1, and a brake B2 including a one-way clutch F1. Hereinafter, regarding the clutch C1, the clutch C2, the brake B1, and the brake B2, they are simply referred to as the engaging device CB without particular distinction.

[0047] The engaging device CB is a known hydraulic friction engaging device, and this known hydraulic friction engaging device includes a multi-plate type or single-plate type clutch, brake, and a band brake tightened by a hydraulic actuator pressed by a hydraulic actuator. Each of the engaging devices CB uses the respective oil pressures of the engaging devices CB, i.e., the CB oil pressure PRcb, adjusted by the hydraulic pressure control circuit 60 (refer to Figure 1 ) provided in the vehicle drive device 10 to change the CB torque Tcb, which is the respective torque capacity, thereby switching the operating states such as the engaged state and the released state, i.e., the control state. The hydraulic pressure control circuit 60 includes a plurality of hydraulic pressure control solenoid valves, oil passage switching solenoid valves, etc. for separately controlling the CB oil pressure PRcb of the plurality of engaging devices CB, and is controlled by an electronic control device 130 described later.

[0048] In the automatic transmission 50, each rotating element of the first planetary gear device 56 and the second planetary gear device 58 is directly or indirectly connected to a part of each other via the engaging device CB and the one-way clutch F1, or is connected to the transmission input shaft 52, the transmission case 42, or the transmission output shaft 54. Each rotating element of the first planetary gear device 56 is a sun gear S1, a carrier CA1, and a ring gear R1, and each rotating element of the second planetary gear device 58 is a sun gear S2, a carrier CA2, and a ring gear R2.

[0049] The automatic transmission 50 is a stepped transmission, and this stepped transmission forms any gear position (also referred to as a gear shift position) among a plurality of gear ratios γat (= AT input speed Ni / AT output speed No) different by engaging any of the engaging devices CB. In the automatic transmission 50, the gear position formed according to the accelerator operation of the driver (= driver), the vehicle speed V, etc. is switched by the electronic control device 130 described later. In the present embodiment, the gear position formed by the automatic transmission 50 is referred to as an AT gear position. The AT input speed Ni is the speed of the transmission input shaft 52, which is the input speed of the automatic transmission 50, and is the same value as the turbine speed Nt, which is the speed of the turbine shaft rotated by the turbine impeller 48b. The AT output speed No is the speed of the transmission output shaft 54, which is the output speed of the automatic transmission 50.

[0050] The automatic transmission 50 is, for example, as Figure 3The working engagement table shows multiple AT gear ratios γat at different values, forming four forward AT gear positions from the AT1st gear position ("1st" in the figure) to the AT4th gear position ("4th" in the figure). The AT1st gear position has the largest gear ratio γat, and the higher the AT gear position on the side of the AT4th gear position that enables high-speed driving, the smaller the gear ratio γat. Figure 3 The working engagement table summarizes the relationship between each AT gear position and each control state of the engagement device CB. In Figure 3 it, "○" indicates engagement, "△" indicates engagement during engine braking and during coasting downshifting of the automatic transmission 50, and a blank space indicates release. The neutral state of the automatic transmission 50 ("N" in the figure) is a state where the automatic transmission 50 cannot transmit power, and this is achieved by setting all to the released state through the engagement device CB and cutting off the power transmission in the automatic transmission 50. In addition, the automatic transmission 50 is set to the neutral state ("Rev" in the figure) when the vehicle 8 is moving backward. When the vehicle 8 is moving backward, power is output from the TF rotary machine MGF, which is the second power source PU2.

[0051] Figure 4 is a diagram showing a schematic structure of the transfer case 28. In Figure 4 it, the transfer case 28 includes a TF input shaft 62, a TF rotary machine MGF, a differential device 64, a TF clutch CF1, a TF brake BF1, a first output shaft 66, an intermediate shaft 68, a first meshing clutch D1, a second meshing clutch D2, and a drive gear 70, etc., which are disposed on a common rotation axis CL1 in the transfer case 44. The differential device 64, the TF clutch CF1, the TF brake BF1, the intermediate shaft 68, the first meshing clutch D1, the second meshing clutch D2, and the drive gear 70 are formed substantially symmetrically with respect to the rotation axis CL1. In Figure 4 it, the lower half is omitted with respect to the rotation axis CL1. The rotation axis CL1 of this transfer case 28 is the same as the rotation axis CL1 of the hybrid transmission 26.

[0052] In addition, the transfer case 28 includes a second output shaft 72 and a driven gear 74, etc., which are disposed on a common rotation axis CL2 in the transfer case 44. The driven gear 74 is formed substantially symmetrically with respect to the rotation axis CL2. Figure 4 In it, the upper half is omitted with respect to the rotation axis CL2. The rotation axis CL2 is the axis of the second output shaft 72, etc.

[0053] In addition, the transfer case 28 includes a rotating machine MGF for TF, a rotating machine connecting gear mechanism 76, a chain 78, etc. inside the transfer case 44. The rotating machine connecting gear mechanism 76 includes a TF rotating machine connecting gear 76a that rotates integrally with the rotor shaft 80 of the rotating machine MGF for TF, an idler gear 76b that always meshes with the TF rotating machine connecting gear 76a, and a TF reaction force input gear 76c that always meshes with the idler gear 76b. The chain 78 is a member that connects the driving gear 70 and the driven gear 74.

[0054] The transfer case 28 also includes a switching actuator 82 fixed to the transfer case 44 (see Figure 1 ). The switching actuator 82 is an actuator for operating the first engagement clutch D1 and the second engagement clutch D2 respectively.

[0055] The TF clutch CF1 and the TF brake BF1 are respectively known wet hydraulic friction engagement devices constituted by multi-plate or single-plate engagement devices pressed by hydraulic actuators. The TF clutch CF1 changes the CF1 torque Tcf1, which is the torque capacity of the TF clutch CF1, by using the CF1 oil pressure PRcf1, which is the regulated oil pressure of the TF clutch CF1 supplied from the oil pressure control circuit 60, thereby switching the control state as the disengaged state. Similarly to the TF clutch CF1, the TF brake BF1 changes the BF1 torque Tbf1 by using the BF1 oil pressure PRbf1 supplied from the oil pressure control circuit 60, thereby switching the control state as the disengaged state. The first engagement clutch D1 and the second engagement clutch D2 are respectively known engagement clutches, i.e., claw clutches. The first engagement clutch D1 and the second engagement clutch D2 respectively switch the control state by controlling the switching actuator 82 by an electronic control device 130 described later.

[0056] The TF input shaft 62 is connected to the transmission output shaft 54 in a power-transmittable manner. The first output shaft 66 is connected to the rear drive shaft 32 in a power-transmittable manner. The second output shaft 72 is connected to the front drive shaft 30 in a power-transmittable manner. The driven gear 74 is fixed to the second output shaft 72 in a non-rotatable relative manner. The TF reaction force input gear 76c is fixed to the intermediate shaft 68 in a non-rotatable relative manner.

[0057] The differential device 64 is composed of a single-pinion type planetary gear device, and includes a sun gear S, a carrier CA, and a ring gear R. The sun gear S is fixed to the intermediate shaft 68 in a non-rotatable manner. Therefore, the TF rotating machine MGF is connected to the sun gear S via the rotating machine connection gear mechanism 76. The carrier CA is fixed to the first output shaft 66 in a non-rotatable manner. The ring gear R is selectively connected to the transfer case 44 via the TF brake BF1. The carrier CA and the ring gear R are selectively connected via the TF clutch CF1. The TF clutch CF1 functions as a differential limiting clutch that rotates the differential device 64 integrally, and can be arranged to connect any two of the sun gear S, the carrier CA, and the ring gear R.

[0058] The first engagement clutch D1 includes a first engagement tooth a1, a second engagement tooth a2, a third engagement tooth a3, and a first sleeve d1s, and is disposed between the TF input shaft 62 that transmits the power of the first power source PU1, the first output shaft 66, and the intermediate shaft 68 connected to the sun gear S. The first engagement tooth a1 is fixed to the TF input shaft 62 in a non-rotatable manner. The second engagement tooth a2 is fixed to the first output shaft 66 in a non-rotatable manner. The third engagement tooth a3 is fixed to the intermediate shaft 68 in a non-rotatable manner. The first sleeve d1s is arranged to be able to move relative to each of the engagement teeth of the first engagement tooth a1, the second engagement tooth a2, and the third engagement tooth a3 in the direction of the rotation axis CL1 (the direction parallel to the rotation axis CL1). The first sleeve d1s has an inner peripheral tooth that can engage with each of the engagement teeth of the first engagement tooth a1, the second engagement tooth a2, and the third engagement tooth a3 in a non-rotatable manner. The first sleeve d1s is moved in the direction of the rotation axis CL1 by the switching actuator 82, so that the engagement state relative to each of the engagement teeth of the first engagement tooth a1, the second engagement tooth a2, and the third engagement tooth a3 changes. In this embodiment, it is switched to the first on-off state [1] in which the first sleeve d1s engages with the first engagement tooth a1 and the second engagement tooth a2 and cuts off the power transmission to the intermediate shaft 68 to connect the TF input shaft 62 and the first output shaft 66, and the second on-off state [2] in which the first sleeve d1s engages with the first engagement tooth a1 and the third engagement tooth a3 and cuts off the power transmission to the first output shaft 66 to connect the TF input shaft 62 and the intermediate shaft 68. The first engagement clutch D1 corresponds to the first on-off device. In addition, in Figure 4 For convenience, a plurality of first sleeves d1s are shown corresponding to the first on-off state [1] and the second on-off state [2] respectively.

[0059] The second engagement clutch D2 includes a fourth engagement tooth a4, a fifth engagement tooth a5, a sixth engagement tooth a6, and a second sleeve d2s, and is disposed between the ring gear R of the differential device 64, the first output shaft 66, and the drive gear 70 connected to the second output shaft 72. The fourth engagement tooth a4 is connected to the ring gear R. The fifth engagement tooth a5 is fixed to the first output shaft 66 so as not to be relatively rotatable. The sixth engagement tooth a6 is connected to the drive gear 70. The second sleeve d2s is arranged to be relatively movable in the direction of the rotation axis CL1 with respect to each of the engagement teeth of the fourth engagement tooth a4, the fifth engagement tooth a5, and the sixth engagement tooth a6. The second sleeve d2s has an inner peripheral tooth that can be engaged with each of the engagement teeth of the fourth engagement tooth a4, the fifth engagement tooth a5, and the sixth engagement tooth a6 so as not to be relatively rotatable. The second sleeve d2s is moved in the direction of the rotation axis CL1 by a switching actuator 82, so that the engagement state with each of the engagement teeth of the fourth engagement tooth a4, the fifth engagement tooth a5, and the sixth engagement tooth a6 changes. In the present embodiment, it is switched to a first on / off state [1] in which the second sleeve d2s is not engaged with any of the fourth engagement tooth a4, the fifth engagement tooth a5, and the sixth engagement tooth a6 and all power transmissions between the ring gear R, the first output shaft 66, and the drive gear 70 are cut off, a second on / off state [2] in which the second sleeve d2s is engaged with the fourth engagement tooth a4 and the sixth engagement tooth a6 and the power transmission with the first output shaft 66 is cut off to connect the ring gear R and the drive gear 70, and a third on / off state [3] in which the second sleeve d2s is engaged with the fifth engagement tooth a5 and the sixth engagement tooth a6 and the power transmission with the ring gear R is cut off to connect the first output shaft 66 and the drive gear 70. The second engagement clutch D2 corresponds to the second on / off device. In addition, in Figure 4 , for convenience, a plurality of second sleeves d2s are shown corresponding to the first on / off state [1], the second on / off state [2], and the third on / off state [3] respectively.

[0060] Figure 5 is a collinear diagram showing the relative relationship of the rotational speeds of the respective rotating elements in the transfer case 28. In Figure 5Among them, the three vertical lines Y1, Y2, and Y3 corresponding to the three rotating elements of the differential device 64 that constitutes the transfer case 28 are, from the left, axes respectively representing the rotational speed of the sun gear S corresponding to the first rotating element RE1, the rotational speed of the carrier CA corresponding to the second rotating element RE2, and the rotational speed of the ring gear R corresponding to the third rotating element RE3. The intervals between the vertical lines Y1 to Y3 are determined according to the gear ratio γg of the differential device 64 (= number of teeth of the sun gear S / number of teeth of the ring gear R). Specifically, when the interval between the vertical line Y1 and the vertical line Y2 is set to 1, the interval between the vertical line Y2 and the vertical line Y3 is the gear ratio γg. The vertical line Y0 shown to the left of the vertical line Y1 is an axis representing the first output shaft 66 corresponding to the input / output rotating element REIO, and its rotational speed is the same as the rotational speed of the carrier CA corresponding to the second rotating element RE2 of the differential device 64.

[0061] If expressed using Figure 5 a collinearity diagram, in the transfer case 28, the input / output rotating element REIO is selectively connected to the TF input shaft 62 via the first engagement clutch D1 (refer to the first on / off state [1]), and is connected to the rear drive shaft 32. The TF input shaft 62 is connected to the first power source PU1 including the engine 12 via the hybrid transmission 26 in a power transmissible manner. In addition, in the differential device 64, the first rotating element RE1 is connected to the TF motor-generator MGF in a power transmissible manner, and is selectively connected to the TF input shaft 62 via the first engagement clutch D1 (refer to the second on / off state [2]), the second rotating element RE2 is connected to the first output shaft 66, and is selectively connected to the second output shaft 72, i.e., the front drive shaft 30, via the second engagement clutch D2 (refer to the third on / off state [3]), the third rotating element RE3 is selectively connected to the second output shaft 72 via the second engagement clutch D2 (refer to the second on / off state [2]), and is selectively connected to the transfer case 44 via the TF brake BF1. In addition, the second rotating element RE2 and the third rotating element RE3 are selectively connected via the TF clutch CF1. In the differential device 64, the relationship between the rotational speeds of the first rotating element RE1, the second rotating element RE2, and the third rotating element RE3 is represented by a straight line Lcd. The first output shaft 66 is an output shaft that inputs power from the first power source PU1 via the hybrid transmission 26 and outputs power to the rear wheels 16. The second output shaft 72 is an output shaft that outputs power to the front wheels 14.

[0062] In the differential device 64, when the TF clutch CF1 is engaged and the TF brake BF1 is released, the first rotating element RE1, the second rotating element RE2, and the third rotating element RE3 rotate integrally. On the other hand, in the differential device 64, when the TF clutch CF1 is released and the TF brake BF1 is engaged, if the first rotating element RE1 is used as the input member and the second rotating element RE2 is used as the output member, the rotational speed of the second rotating element RE2 is decelerated with respect to the rotational speed of the first rotating element RE1. Therefore, the differential device 64 functions as a transmission that selectively forms a high gear achieved when the TF clutch CF1 is engaged and a low gear achieved when the TF brake BF1 is engaged.

[0063] In addition, when both the TF clutch CF1 and the TF brake BF1 are set to the released state, the differential device 64 can exert a differential action. Therefore, the differential device 64 functions as a center differential. At this time, in the transfer case 28, when the first engagement clutch D1 is in the first on / off state [1] and the second engagement clutch D2 is in the second on / off state [2], the differential device 64 can distribute the torque from the first power source PU1 input to the second rotating element RE2 to the third rotating element RE3 by using the reaction torque of the TF rotating machine MGF connected to the first rotating element RE1. In addition, instead of causing the reaction torque of the TF rotating machine MGF to act, the differential device 64 restricts the differential action of the differential device 64 by making the TF clutch CF1 slip, so that the torque from the first power source PU1 input to the second rotating element RE2 can be distributed to the third rotating element RE3. In this way, the transfer case 28 is a power distribution device that distributes a part of the torque from the first power source PU1 input to the first output shaft 66 to the second output shaft 72. As a result, in the transfer case 28, torque can be distributed to the front wheels 14 and the rear wheels 16. In addition, when the second engagement clutch D2 is set to the third on / off state [3] in the transfer case 28, the differential device 64 is set to a differential lock state in which it does not function as a center differential.

[0064] Figure 6 It is an operation engagement table showing the relationship between the multiple driving modes established in the transfer case 28 and the control states of the respective engagement devices in the transfer case 28. In Figure 6 it, "○" in the columns of the TF brake BF1 and the TF clutch CF1 indicates engagement, and the blank column indicates release. In addition, "○" in the columns of the first engagement clutch D1 and the second engagement clutch D2 indicates the on / off state of each engagement clutch and the engaged teeth.

[0065] The "EV(FR) high" mode with number m1 and the "EV(FR) low" mode with number m2 are achieved by engaging only one of the TF clutch CF1 and the TF brake BF1, and setting the first engagement clutch D1 to the first on / off state [1], and setting the second engagement clutch D2 to the first on / off state [1]. The "EV(FR) high" mode and the "EV(FR) low" mode are, for example, EV driving modes that can perform motor driving (= EV driving) in a state where the operation of the first power source PU1 is stopped and only the TF rotating machine MGF is used as the power source. The second engagement clutch D2 is set to the first on / off state [1], so that the engagement between the fourth engagement tooth a4, the fifth engagement tooth a5, and the sixth engagement tooth a6 is set to the neutral state (refer to "N" in the figure). Therefore, in the differential device 64, the power transmission path to the front wheels 14 is cut off. In this state, in the differential device 64 where a high gear is formed based on the engaged state of the TF clutch CF1 or a low gear is formed based on the engaged state of the TF brake BF1, the power from the TF rotating machine MGF is transmitted to the rear wheel 16 side. Thus, the EV driving of this embodiment is achieved by rear-wheel drive. In the EV driving mode, for example, when the first engagement clutch D1 is in the first on / off state [1], the engine on / off clutch K0 is released, or the automatic transmission 50 is set to the neutral state, so that the drag of the engine 12 can be eliminated. Or, if the first engagement clutch D1 can be set to the released state, then in the EV driving mode, for example, the first engagement clutch D1 is set to the released state, so that regardless of the state of the engine on / off clutch K0 and the automatic transmission 50, the drag of the automatic transmission 50 and the engine 12 can be eliminated. Figure 6 The "(○)" means that in the case where the first engagement clutch D1 can be set to the released state (neutral state), it can also be this released state. In addition, the first engagement clutch D1 can also be in the second on / off state [2], but considering mode switching such as the "H4_torque separation" mode and the "H4_LSD" mode, it is set to the first on / off state [1].

[0066] The "H4_torque separation" mode with number m3 is achieved by setting both the TF clutch CF1 and the TF brake BF1 to the released state, setting the first engagement clutch D1 to the first on / off state [1], and setting the second engagement clutch D2 to the second on / off state [2]. The "H4_torque separation" mode is as follows: in a state where the differential device 64 is in the same state as the high gear range, that is, the first to third rotating elements RE1 to RE3 rotate at substantially the same speed, a reaction torque (negative torque) is applied to the first rotating element RE1 by the TF rotating machine MGF, so that the torque from the first power source PU1 transmitted from the first output shaft 66 to the second rotating element RE2 is transmitted to the third rotating element RE3 at an arbitrary desired ratio corresponding to the reaction torque of the TF rotating machine MGF, and the torque is distributed to the front wheels 14 and the rear wheels 16. In the "H4_torque separation" mode in the transfer case 28, power generation control (also called regeneration control) is performed on the TF rotating machine MGF to generate a reaction torque.

[0067] Figure 7It is a collinear diagram in the case of the above-mentioned "H4_Torque Separation" mode. The TF input torque Ttfin is transmitted from the first power source PU1, which is the power source of this mode, to the first output shaft 66 via the first engagement clutch D1, and the MGF torque Tmgf, which is the generating torque of the TF motor-generator MGF, is applied to the first rotating element RE1 of the differential device 64. The differential device 64 can perform differential rotation, and the TF input torque Ttfin acts on the second rotating element RE2 in the positive rotation direction. Therefore, when the MGF torque Tmgf, which is a negative torque, is applied to the first rotating element RE1 as a reaction force, a negative RE2 torque Tre2 is generated as a rotational resistance in the second rotating element RE2, and a positive RE3 torque Tre3 is generated as a driving torque in the third rotating element RE3. The RE2 torque Tre2 and the RE3 torque Tre3 can be expressed by the following equations (1) and (2) respectively using the gear ratio γg of the differential device 64. Then, as shown in equation (3), the torque obtained by applying the RE2 torque Tre2 to the TF input torque Ttfin is output as the rear-wheel side torque Tr from the first output shaft 66 to the rear-wheel 16 side. In addition, as shown in equation (4), the RE3 torque Tre3 is output as the front-wheel side torque Tf from the second output shaft 72 to the front-wheel 14 side. That is, a part of the TF input torque Ttfin transmitted from the first power source PU1 to the first output shaft 66 is distributed to the second output shaft 72 by the transfer case 28 and transmitted to the front-wheel 14 side. The larger the MGF torque Tmgf is, the larger the front-wheel side torque Tf is, and the smaller the rear-wheel side torque Tr is. In addition, the rotation axis of the drive gear 70 connected to the third rotating element RE3 via the second engagement clutch D2 can also be regarded as the second output shaft for power transmission to the front-wheel 14 side. In addition, equation (4) is the case where the number of teeth of the drive gear 70 and the driven gear 74 are equal.

[0068] Tre2 = -(1 + 1 / γg)Tmgf …(1)

[0069] Tre3 = (1 / γg)Tmgf …(2)

[0070] Tr = Ttfin + Tre2 = Ttfin - (1 + 1 / γg)Tmgf …(3)

[0071] Tf = Tre3 = (1 / γg)Tmgf …(4)

[0072] Figure 6The "H4_LSD" mode with number m4 is achieved by controlling the TF clutch CF1 to a slipping state while the TF brake BF1 is set to the released state, the first engagement clutch D1 is set to the first on / off state [1], and the second engagement clutch D2 is set to the second on / off state [2]. The "H4_LSD" mode is a mode in which, instead of the reaction torque of the TF rotating machine MGF in the "H4_torque separation" mode, a part of the TF input torque Ttfin transmitted to the first output shaft 66 is transmitted from the third rotating element RE3 to the second output shaft 72 through the restriction of the differential action of the differential device 64 based on the slipping state of the TF clutch CF1, and the torque is distributed to the front wheels 14 and the rear wheels 16 at an arbitrary desired ratio corresponding to the torque capacity of the TF clutch CF1.

[0073] The "H4_Lock" mode with number m5 is achieved by setting both the TF clutch CF1 and the TF brake BF1 to the released state, the first engagement clutch D1 to the first on / off state [1], and the second engagement clutch D2 to the third on / off state [3]. The "H4_Lock" mode is a mode in which, with the first output shaft 66 and the second output shaft 72 directly connected and the differential device 64 substantially set to the differential lock state, the TF input torque Ttfin transmitted from the first power source PU1 to the first output shaft 66 through the first engagement clutch D1 is distributed to the front wheels 14 and the rear wheels 16.

[0074] The "L4_Lock" mode with number m6 is achieved by setting the TF clutch CF1 to the released state, the TF brake BF1 to the engaged state, the first engagement clutch D1 to the second on / off state [2], and the second engagement clutch D2 to the third on / off state [3]. The "L4_Lock" mode is a mode in which, with the first output shaft 66 and the second output shaft 72 directly connected, the differential device 64 substantially set to the differential lock state and set to the low gear, the TF input torque Ttfin transmitted from the first power source PU1 to the sun gear S of the differential device 64 is distributed from the carrier CA as the second rotating element RE2 to the front wheels 14 and the rear wheels 16.

[0075] Return to Figure 1 , the vehicle drive device 10 includes a MOP84 as a mechanical oil pump, an EOP86 as an electric oil pump, a pump motor 88, etc. The MOP84 is connected to the rotating machine connecting shaft 46 (refer to Figure 2) The first power source PU1 is rotationally driven to discharge the working oil OIL used in the power transmission device 18. The pump motor 88 is a dedicated motor for the EOP86 that rotationally drives the EOP86. The EOP86 is rotationally driven by the pump motor 88 to discharge the working oil OIL. The working oil OIL discharged from the MOP84 and the EOP86 is supplied to the hydraulic control circuit 60. The hydraulic control circuit 60 supplies the CB hydraulic pressure PRcb, the CF1 hydraulic pressure PRcf1, the BF1 hydraulic pressure PRbf1, etc., which are respectively pressure-regulated according to the working oil OIL discharged from the MOP84 and / or the EOP86.

[0076] The vehicle drive device 10 includes an electronic control device 130 that is a controller serving as a control device including the control of the first power source PU1, the second power source PU2, the transfer case 28, and the like. Figure 1 It is a diagram showing the input / output system of the electronic control device 130 and is also a functional block diagram illustrating the main part of the control function based on the electronic control device 130. The electronic control device 130 is configured, for example, to include a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, etc. The CPU uses the temporary storage function of the RAM and performs signal processing in accordance with a program pre-stored in the ROM, thereby executing various controls of the vehicle drive device 10. The electronic control device 130 is configured to include various computers for engine control, transmission control, etc. as needed.

[0077] Various signals based on the detection values obtained from various sensors etc. (such as engine speed sensor 90, MGM speed sensor 92, turbine speed sensor 94, AT output speed sensor 96, vehicle speed sensor 98, MGF speed sensor 100, accelerator opening sensor 102, throttle valve opening sensor 104, brake pedal sensor 106, shift position sensor 108, acceleration sensor 110, yaw rate sensor 112, steering sensor 114, battery sensor 116, oil temperature sensor 118, differential lock selection switch 120, low gear selection switch 122, etc.) provided in the vehicle drive device 10 are respectively supplied to the electronic control device 130. (For example, engine speed Ne which is the speed of the engine 12, MGM speed Nmgm which is the speed of the TM rotary machine MGM, turbine speed Nt which is the same value as the AT input speed Ni, AT output speed No, TF output speed Nof which is the speed of the first output shaft 66 corresponding to the vehicle speed V, MGF speed Nmgf which is the speed of the TF rotary machine MGF, accelerator opening θacc which is the accelerator operation amount of the driver indicating the acceleration demand or drive demand of the driver, throttle valve opening θth which is the opening of the electronic throttle valve, brake on signal Bon which is a signal indicating the state where the brake pedal for operating the wheel brake is operated by the driver, shift operation position POSsh indicating the operation position of the shift lever provided in the vehicle 8, longitudinal acceleration Gx and lateral acceleration Gy of the vehicle 8, yaw rate Ryaw which is the rotational angular velocity of the vehicle 8 about the vertical axis, steering angle θsw and steering direction Dsw of the steering wheel provided in the vehicle 8, battery temperature THbat of the battery 24, battery charge / discharge current Ibat, battery voltage Vbat, working oil temperature THoil which is the temperature of the working oil OIL, lock mode on signal LOCKon which is a signal indicating that the driver selects the "H4_Lock" mode or the "L4_Lock" mode, low gear on signal LOWon which is a signal indicating that the driver selects the low gear of the differential device 64, etc.)

[0078] The differential lock selection switch 120 and the low gear selection switch 122 are provided near the driver's seat, for example. The differential lock selection switch 120 is a switch that is operated by the driver to the on state when the differential device 64 is set to the differential lock state in the transfer case 28. The low gear selection switch 122 is a switch that is operated by the driver to the on state when the differential device 64 is set to the low gear when the "H4_Lock" mode is established in the transfer case 28.

[0079] Various command signals (such as an engine control command signal Se for controlling the engine 12, an MGM control command signal Smgm for controlling the TM rotary machine MGM, an MGF control command signal Smgf for controlling the TF rotary machine MGF, a hydraulic pressure control command signal Sat for controlling the control state of the engagement device CB related to the control of the automatic transmission 50, a hydraulic pressure control command signal Scbf for controlling the control states of the TF clutch CF1 and the TF brake BF1 related to the control of the transfer case 28, a transfer case control command signal Stf for operating the first engagement clutch D1 and the second engagement clutch D2 related to the control of the transfer case 28 respectively, an EOP control command signal Seop for controlling the EOP 86, a brake control command signal Sb for controlling the braking force based on the wheel brakes, an information report control command signal Sinf for reporting various information to the driver, etc.) are output from the electronic control device 130 to each device (such as the engine control device 20, the inverter 22, the hydraulic pressure control circuit 60, the switching actuator 82, the pump motor 88, the wheel brake device 124, the information report device 126, etc.) provided in the vehicle 8. The information report device 126 is a display device, a sound emitting device, etc. that inform various information through images and sounds.

[0080] In order to achieve various controls in the vehicle drive device 10, the electronic control device 130 includes an AT shift control unit, i.e., an AT shift control section 132, a hybrid control unit, i.e., a hybrid control section 134, and a drive state control unit, i.e., a drive state control section 140.

[0081] The AT shift control section 132, for example, uses an AT shift map as shown in Figure 8 to perform shift determination of the automatic transmission 50, and outputs a hydraulic pressure control command signal Sat for executing the shift control of the automatic transmission 50 to the hydraulic pressure control circuit 60 as needed. The AT shift map is a relationship obtained and stored in advance through experiments or designs, i.e., a predetermined relationship. The AT shift map is, for example, a predetermined relationship having shift lines for determining the shift of the automatic transmission 50 on a two-dimensional coordinate with the vehicle speed V and the required drive torque Trdem as variables. In the AT shift map, the AT output speed No, etc. can be used instead of the vehicle speed V, and the required driving force Frdem, the accelerator opening θacc, the throttle valve opening θth, etc. can be used instead of the required drive torque Trdem. Each shift line in the AT shift map is an upshift line for determining upshifting as shown by the solid line and a downshift line for determining downshifting as shown by the dashed line.

[0082] The hybrid control unit 134 functionally includes an engine control unit, i.e., the engine control section 136, which controls the operation of the engine 12, and a rotary machine control unit, i.e., the rotary machine control section 138, which controls the operations of the TM rotary machine MGM and the TF rotary machine MGF via the inverter 22. Using these control functions, it performs hybrid drive control and the like carried out by the engine 12, the TM rotary machine MGM, and the TF rotary machine MGF.

[0083] The hybrid control unit 134 calculates the driver's driving demand for the vehicle 8 by applying the accelerator opening θacc and the vehicle speed V to, for example, a drive demand map that is a pre-determined relationship. The drive demand is, for example, the required drive torque Trdem [Nm] in the drive wheels (front wheels 14, rear wheels 16). As the drive demand, it is also possible to use the required driving force Frdem [N] in the drive wheels, the required drive power Prdem [W] in the drive wheels, the required AT output torque in the output shaft 54 of the transmission, and the like. From another perspective, the required drive torque Trdem is the required drive power Prdem at the vehicle speed V at the time of command output. In the calculation of the drive demand, it is also possible to use the TF output speed Nof or the like instead of the vehicle speed V.

[0084] The hybrid control unit 134 outputs an engine control command signal Se, an MGM control command signal Smgm, and an MGF control command signal Smgf in a manner that realizes the required drive power Prdem, taking into account transmission losses, accessory loads, the gear ratio γat of the automatic transmission 50, the rechargeable power Win of the battery 24, the dischargeable power Wout, and the like. The engine control command signal Se is, for example, a command value for the required engine power Pedem, which is a required value for the engine power Pe that realizes the engine torque Te at the engine speed Ne at the time of output command output. The engine power Pe is the output [W], i.e., the power, of the engine 12. The MGM control command signal Smgm is, for example, a command value for the power consumption Wcmgm or the generated power Wgmgm of the TM rotary machine MGM for the MGM torque Tmgm at the MGM speed Nmgm at the time of output command output. The MGF control command signal Smgf is, for example, a command value for the power consumption Wcmgf or the generated power Wgmgf of the TF rotary machine MGF for the MGF torque Tmgf at the MGF speed Nmgf at the time of output command output.

[0085] The rechargeable power Win of the storage battery 24 is the maximum power that can be input, which defines the limit of the input power of the storage battery 24 and represents the input limit of the storage battery 24. The dischargeable power Wout of the storage battery 24 is the maximum power that can be output, which defines the limit of the output power of the storage battery 24 and represents the output limit of the storage battery 24. The rechargeable power Win and the dischargeable power Wout of the storage battery 24 are calculated by the electronic control unit 130 based on, for example, the battery temperature THbat and the state of charge value SOC [%] of the storage battery 24. The state of charge value SOC of the storage battery 24 represents the remaining charge amount with a value indicating the state of charge corresponding to the charge amount of the storage battery 24, and is calculated by the electronic control unit 130 based on, for example, the battery charge and discharge current Ibat and the battery voltage Vbat, etc.

[0086] When the required driving power Prdem is in the motor driving region smaller than a predetermined threshold value, the hybrid control unit 134 enables the EV driving mode. On the other hand, when the required driving power Prdem is in the engine driving region equal to or greater than the predetermined threshold value, the hybrid control unit 134 enables the HV driving mode in which engine driving is possible. Figure 8 The dotted line LA is the boundary line between the engine driving region and the motor driving region, that is, the driving mode switching line. It has the following Figure 8 predetermined relationship as shown by the dotted line LA. It is an example of a driving mode switching map composed of a two-dimensional coordinate with the vehicle speed V and the required driving torque Trdem as variables. The Figure 6 numbers m1 and m2 are the EV driving modes, and the numbers m3 to m6 are the HV driving modes. In addition, in Figure 8 , for convenience, the driving mode switching map is shown together with the AT gear shift map.

[0087] Even when the required driving power Prdem is in the motor driving region, the hybrid control unit 134 enables the HV driving mode when the state of charge value SOC of the storage battery 24 is less than a predetermined engine start threshold value, when engine warm-up of the engine 12 is required, etc. From another perspective, when the state of charge value SOC of the storage battery 24 is less than the engine start threshold value, or when engine warm-up of the engine 12 is required, the motor driving region in the driving region switching map disappears. The engine start threshold value is a predetermined threshold value of the state of charge value SOC for determining whether it is necessary to automatically start the engine 12 to charge the storage battery 24.

[0088] The drive state control unit 140 determines, for example, based on the vehicle speed V, accelerator opening θacc, brake-on signal Bon, shift operation position POSsh, longitudinal acceleration Gx and lateral acceleration Gy, yaw rate Ryaw, steering angle θsw and steering direction Dsw, lock mode-on signal LOCKon, low-speed gear-on signal LOWon, etc., which driving mode among the various driving modes in the transfer case 28 (refer to Figure 6 ) is to be established, and outputs various control command signals for establishing the determined driving mode. The various control command signals in this case are, for example, the hydraulic pressure control command signal Scbf for the TF clutch CF1 and the TF brake BF1, and the transfer case control command signal Stf for the first engagement clutch D1 and the second engagement clutch D2.

[0089] In the EV driving mode, the drive state control unit 140, for example, sets the TF brake BF1 in the engaged state and the TF clutch CF1 in the released state in a relatively low vehicle speed range to form a low gear in the differential device 64, setting it to the "EV(FR) low" mode. On the other hand, in a relatively high vehicle speed range, the drive state control unit 140 sets the TF brake BF1 in the released state and the TF clutch CF1 in the engaged state to form a high gear in the differential device 64, setting it to the "EV(FR) high" mode. That is, in the EV driving mode, the drive state control unit 140, for example, makes the "EV(FR) low" mode established in a relatively low vehicle speed range, and on the other hand, makes the "EV(FR) high" mode established in a relatively high vehicle speed range.

[0090] In the "H4_torque split" mode, the drive state control unit 140, for example, determines the driving state of the vehicle 8 based on various signals from various sensors such as the vehicle speed sensor 98, acceleration sensor 110, yaw rate sensor 112, etc., and sets a target distribution ratio Rdis as the target value of the torque distribution ratio Rx corresponding to the determined driving state. The torque distribution ratio Rx is the ratio of the torque Tr on the rear wheel side to the torque Tf on the front wheel side, which is the ratio of the torque distributed to the first output shaft 66 and the second output shaft 72. The torque distribution ratio Rx can be represented, for example, by the rear wheel side distribution ratio Xr, which is the ratio of the rear wheel side torque Tr to the total torque Trf (=Tr + Tf) of the rear wheel side torque Tr and the front wheel side torque Tf. Alternatively, the torque distribution ratio Rx can be represented, for example, by the front wheel side distribution ratio Xf (=1 - Xr), which is the ratio of the front wheel side torque Tf to the total torque Trf (=Tr + Tf) of the rear wheel side torque Tr and the front wheel side torque Tf. The torque distribution ratio Rx corresponds to the power distribution ratio.

[0091] The drive state control unit 140 includes a torque separation control unit 142 that executes various controls when driving in the "H4_torque separation" mode. The torque separation control unit 142 performs power generation control of the MGF torque Tmgf of the TF rotary machine MGF in such a way that the torque distribution ratio Rx becomes the target distribution ratio Rdis as the target value, and controls the total torque Tpu1 of the engine 12 and the TM rotary machine MGM that constitute the first power source PU1 in such a way that the required drive torque Trdem is obtained regardless of the MGF torque Tmgf. That is, the ratio of the rear-wheel-side torque Tr represented by the above formula (3) to the front-wheel-side torque Tf represented by the above formula (4) becomes the target distribution ratio Rdis, and the MGF torque Tmgf and the TF input torque Ttfin are obtained in such a way that the required drive torque Trdem is obtained using the total torque Trf obtained by combining the rear-wheel-side torque Tr and the front-wheel-side torque Tf, and the total torque Tpu1 of the first power source PU1 is determined according to the AT gear position of the automatic transmission 50 in such a way as to obtain the TF input torque Ttfin. The torque separation control unit 142 outputs an MGF control command signal Smgf for generating power of the TF rotary machine MGF using the MGF torque Tmgf to the inverter 22, and outputs an engine control command signal Se and an MGM control command signal Smgm for operating the engine 12 and the TM rotary machine MGM that constitute the first power source PU1 using the above total torque Tpu1 to the engine control device 20 and the inverter 22. The control of the engine 12 and the TM rotary machine MGM can be performed via the hybrid control unit 134, but it is also possible for the torque separation control unit 142 to perform it directly prior to the hybrid control unit 134. Specifically, the MGF control command signal Smgf is a command value for the generated power Wgmgf of the TF rotary machine MGF required to output the MGF torque Tmgf. The larger the MGF torque Tmgf of the TF rotary machine MGF, the larger the front-wheel-side distribution ratio Xf, and thus the smaller the rear-wheel-side distribution ratio Xr.

[0092] Hereinafter, the MGF torque Tmgf as the above target distribution ratio Rdis is referred to as the MGF torque TDmgf at the time of distribution, and the generated power Wgmgf is referred to as the generated power WDgmgf at the time of distribution. In addition, the MGM torque Tmgm of the TM rotary machine MGM driven using the generated power WDgmgf at the time of distribution is referred to as the MGM torque TDmgm at the time of distribution, and the consumed power Wcmgm is referred to as the consumed power WDcmgm at the time of distribution.

[0093] In the "H4_LSD" mode, the drive state control unit 140 outputs an oil pressure control command signal Scbf for controlling the slip state (i.e., torque capacity) of the TF clutch CF1 to the oil pressure control circuit 60 in such a manner that the torque distribution ratio Rx becomes the target distribution ratio Rdis. The larger the torque capacity of the TF clutch CF1, the larger the front-wheel side distribution ratio Xf, and thus the smaller the rear-wheel side distribution ratio Xr.

[0094] In the "H4_Torque Separation" mode and the "H4_LSD" mode, when the differential lock selection switch 120 is operated by the driver to the ON state, the drive state control unit 140 switches the second engagement clutch D2 from the second on / off state [2] to the third on / off state [3], causing the "H4_Lock" mode to be established. In the "H4_Lock" mode, when the low-speed gear selection switch 122 is operated by the driver to the ON state while the vehicle 8 is stopped, the drive state control unit 140 switches the first engagement clutch D1 from the first on / off state [1] to the second on / off state [2], causing the "L4_Lock" mode to be established.

[0095] Here, during traveling in the "H4_Torque Separation" mode, the distribution-time generated power WDgmgf obtained by the power generation control of the TF rotating machine MGF is generally charged to the battery 24, taken out from the battery 24 according to the traveling conditions, and utilized in the power running control of using the TM rotating machine MGM and the TF rotating machine MGF as electric motors. However, when power is transferred via the battery 24, power loss occurs during charging and discharging. In contrast, in the present embodiment, the torque separation control unit 142 that executes various controls during traveling in the "H4_Torque Separation" mode functionally includes a power consumption control unit 144 and a charging control unit 146 for the processing of the distribution-time generated power WDgmgf obtained during the power generation control of the TF rotating machine MGF, and executes signal processing according to Figure 9 the flowchart. Figure 9 Steps S3, S4, S5, S6, and S7 of

[0096] correspond to the power consumption control unit 144, and step S9 corresponds to the charging control unit 146. Figure 9In step S1, it is determined whether the vehicle is traveling in the torque separation mode. In this embodiment, it is determined whether the vehicle is traveling in the "H4_Torque Separation" mode. If it is not in the "H4_Torque Separation" mode, the process directly ends. When the vehicle is traveling in the "H4_Torque Separation" mode, the steps after step S2 are executed. In step S2, it is determined whether the state of charge value SOC of the battery 24 is greater than a predetermined determination value α. If SOC > α, the steps after step S6 are executed. The determination value α is, for example, the state of charge value SOC of the battery 24 at full charge when it is not suitable for continued charging. However, from the perspective of energy efficiency, compared with the case of temporarily charging the battery 24, the overall efficiency is better when using the TM motor-generator MGM. Therefore, a predetermined state of charge value SOC smaller than full charge can also be set as the determination value α.

[0097] In step S6, the distributed generation power WDgmgf obtained by the power generation control of the TF motor-generator MGF is supplied to the TM motor-generator MGM without passing through the battery 24 to drive the TM motor-generator MGM. That is, by directly using the distributed generation power WDgmgf obtained by the TF motor-generator MGF as the distributed consumption power WDcmgm of the TM motor-generator MGM, the MGM torque Tmgm is increased by the distributed MGM torque TDmgm based on the distributed consumption power WDcmgm. For example, in the HV driving mode including the "H4_Torque Separation" mode, when substantially all of the engine torque Te is used to generate the total torque Tpu1 of the first power source PU1 required to obtain the required drive torque Trdem, the TM motor-generator MGM is rotationally driven with the above-mentioned distributed consumption power WDcmgm. In the HV driving mode, when the total torque Tpu1 is generated by using both the engine 12 and the TM motor-generator MGM through motor assistance or the like, it is only necessary to increase the consumption power Wcmgm of the TM motor-generator MGM by the distributed consumption power WDcmgm equivalent to the distributed generation power WDgmgf obtained by the power generation control of the TF motor-generator MGF. Alternatively, the consumption power Wcmgm of the TM motor-generator MGM based on motor assistance can also be supplied from the distributed generation power WDgmgf, and the share from the battery 24 can be reduced accordingly.

[0098] In the next step S7, when a part of the power generation power WDgmgf obtained by the power generation control of the rotating machine MGF by TF remains, the remaining power Wsur is charged to the storage battery 24. When step S6 is executed when the charge state value SOC is larger than the determination value α, the rotating machine MGM for TM is operated as much as possible using the power generation power WDgmgf at the time of distribution. Therefore, basically the remaining power Wsur = 0, and the next step S8 is executed without performing the charge control of the storage battery 24. In step S8, the operating point of the engine 12 is changed in such a way that the total torque Tpu1 of the first power source PU1 does not change regardless of the increase in the MGM torque Tmgm based on the power generation power WDgmgf at the time of distribution. The operating point of the engine 12 represents the operating state of the engine 12, and in the present embodiment, it is defined by the engine speed Ne and the engine torque Te. The engine speed Ne is determined according to the vehicle speed V, the AT gear of the automatic transmission 50, etc. Therefore, the engine torque Te is decreased by the increased amount of the MGM torque Tmgm based on the power generation power WDgmgf at the time of distribution (the MGM torque TDmgm at the time of distribution).

[0099] When the determination in step S2 is NO (negative), that is, when the charge state value SOC of the storage battery 24 is equal to or less than the determination value α, there is room for charging the storage battery 24, so the steps after step S3 are executed. In step S3, the power generation power WDgmgf at the time of distribution, which is the amount of power generation when the MGF torque TDmgf for which the torque distribution ratio Rx becomes the target distribution ratio Rdis is used to control the power generation of the TF rotating machine MGF, is calculated. In step S4, the MGM torque Tmgm when all of the power generation power WDgmgf at the time of distribution is directly used as the consumption power Wcmgm of the rotating machine MGM for TM is calculated as the MGM torque TDmgm at the time of distribution. Then, in step S5, based on the MGM torque TDmgm at the time of distribution, it is determined whether the MGM torque Tmgm can be increased in such a way that the operating point of the engine 12 approaches Figure 10 the best fuel economy line Lfl.

[0100] In Figure 10 it, the best fuel economy line Lfl shown by the solid line is a predetermined operation curve of the engine 12 showing the relationship between the engine speed Ne and the engine torque Te with the best fuel economy of the engine 12, and is a connection line of the best fuel economy operating points, representing the best fuel economy state. Figure 10The multiple elliptical dashed lines are equal fuel economy lines. The smaller the ellipse, the better the fuel economy. On the other hand, the double-dashed line is an example of an equal power line of the required engine power Pedem that can achieve the required drive power Prdem calculated based on the accelerator opening θacc, etc. In this case, when the engine speed Ne determined according to the vehicle speed V, the AT gear of the automatic transmission 50, etc. is Ne1, the intersection point A with the equal power line of the required engine power Pedem is the operating point of the engine 12. In Figure 10 this case, the engine torque Tea at the operating point A is larger than the engine torque Teb at the operating point B on the best fuel economy line Lfl. Therefore, it is possible to use the MGM torque TDmgm during distribution of the TM motor / generator MGM to decrease the engine torque Te and make the operating point approach the best fuel economy line Lfl, and the determination in step S5 becomes Yes (positive).

[0101] When the determination in step S5 is Yes, steps S6 to S8 are executed. The TM motor / generator MGM is rotationally driven using the generated power WDgmgf during distribution, and the operating point of the engine 12 is made to approach the best fuel economy line Lfl. For example, when the differential torque ΔTe (= Tea - Teb) between the engine torque Tea at the operating point A and the engine torque Teb at the operating point B is equal to the MGM torque TDmgm during distribution obtained in step S4, in step S6, all of the generated power WDgmgf during distribution is supplied to the TM motor / generator MGM, and the TM motor / generator MGM is rotationally driven using the MGM torque TDmgm during distribution. And in step S8, the engine 12 is operated at the operating point B on the best fuel economy line Lfl. When the differential torque ΔTe is larger than the MGM torque TDmgm during distribution, in step S6, all of the generated power WDgmgf during distribution is supplied to the TM motor / generator MGM, and the TM motor / generator MGM is rotationally driven using the MGM torque TDmgm during distribution. And in step S8, at the operating point of the engine torque Te (= Tea - TDmgm) obtained by subtracting the MGM torque TDmgm during distribution from the engine torque Tea, that is Figure 10The operating point between point A and point B in [description] causes the engine 12 to operate. Additionally, when the differential torque ΔTe is smaller than the MGM torque TDmgm during distribution, in step S6, the amount of power consumption Wcmgm required to rotationally drive the TM rotary machine MGM with an MGM torque Tmgm that matches the differential torque ΔTe is supplied with the generated power WDgmgf during distribution to the TM rotary machine MGM. The TM rotary machine MGM is rotationally driven with this power consumption Wcmgm, and in step S8, the engine 12 is operated at the operating point B on the best fuel economy line Lfl. In this case, only a part of the generated power WDgmgf during distribution is consumed as the power consumption Wcmgm of the TM rotary machine MGM, so the remaining surplus power Wsur (= WDgmgf - Wcmgm) is charged to the storage battery 24 in step S7.

[0102] On the other hand, when the required engine power Pedem is smaller than Figure 10 the double-dot dash line, and the operating point of the engine 12 is Figure 10 at points B and C, that is, when the engine torque Te is on or smaller than the best fuel economy line Lfl, even if the generated power WDgmgf during distribution is supplied to the TM rotary machine MGM for rotational drive, it is not possible to bring the operating point of the engine 12 closer to the best fuel economy line Lfl. Therefore, the determination in step S5 becomes No (negative), and step S9 is executed to charge all of the generated power WDgmgf during distribution to the storage battery 24. Additionally, even when the operating point of the engine 12 is at points B and C, in the case of performing motor assistance based on the TM rotary machine MGM, the power consumption Wcmgm of the TM rotary machine MGM can be supplied from the generated power WDgmgf during distribution, and the surplus power Wsur (= WDgmgf - Wcmgm) is charged to the storage battery 24 in step S9.

[0103] In such a vehicle drive device 10, during the control of the power generation of the MGF torque TDmgf such that the torque distribution ratio Rx becomes the target distribution ratio Rdis and the torque split control unit 142 that controls the total torque Tpu1 of the first power source PU1 such that the required drive torque Trdem is obtained regardless of the MGF torque TDmgf during distribution includes a power consumption control unit 144. When it is possible to drive the TM motor MGM by using a part or all of the power generation power WDgmgf during distribution obtained by the power generation control and bring the operating point of the engine 12 closer to the fuel economy optimal line Lfl (the determination in step S5 is "Yes"), a part or all of the power generation power WDgmgf during distribution is supplied to the TM motor MGM without passing through the battery 24 to drive the TM motor MGM. Therefore, compared with the case where the power generation power WDgmgf during distribution obtained by the power generation control is always charged to the battery 24, the power loss caused by the charge and discharge of the battery 24 is reduced, and the overall energy efficiency of the vehicle drive device 10 is improved. In addition, the operating point of the engine 12 is brought closer to the fuel economy optimal line Lfl, and the power generation power WDgmgf during distribution obtained by the power generation control is used to drive the TM motor MGM, so the fuel economy of the engine 12 is improved, which also contributes to the improvement of the overall energy efficiency of the vehicle drive device 10.

[0104] In addition, the torque split control unit 142 includes a charge control unit 146 that charges all of the power generation power WDgmgf during distribution obtained by the power generation control to the battery 24, and selects whether to perform control by the power consumption control unit 144 or by the charge control unit 146 according to the operating point of the engine 12. Therefore, the control based on the power consumption control unit 144 is appropriately executed according to the operating point of the engine 12, and the overall energy efficiency of the vehicle drive device 10 can be improved by the control executed by the power consumption control unit 144.

[0105] In addition, it is determined whether it is possible to drive the TM motor MGM by using a part or all of the power generation power WDgmgf during distribution obtained by the power generation control and bring the operating point of the engine 12 closer to the fuel economy optimal line Lfl. When it is possible to bring it closer to the fuel economy optimal line Lfl, the control based on the power consumption control unit 144 is selected. Therefore, the control based on the power consumption control unit 144 is appropriately executed according to the operating point of the engine 12, and the overall energy efficiency of the vehicle drive device 10 can be improved by the control executed by the power consumption control unit 144.

[0106] Further, when the state of charge (SOC) value of the storage battery 24 exceeds a predetermined determination value α, the selection of the operating point of the engine 12 is not performed, and all of the distributed generated power WDgmgf obtained by the power generation control is supplied to the TM rotary machine MGM without passing through the storage battery 24 to drive the TM rotary machine MGM. Therefore, the power loss caused by the charge / discharge and full charge of the storage battery 24 is suppressed.

[0107] Further, when it is possible to drive the TM rotary machine MGM by supplying the distributed generated power WDgmgf obtained by the power generation control to the TM rotary machine MGM and make the operating point of the engine 12 approach the best fuel economy line Lfl, and when a part of the distributed generated power WDgmgf remains, the remaining power Wsur is charged to the storage battery 24. Therefore, the operating point of the engine 12 can be reliably made to approach the best fuel economy line Lfl, and the overall energy efficiency of the vehicle drive device 10 can be appropriately improved.

[0108] As described above, the embodiments of the present invention have been described in detail with reference to the drawings, but this is merely one embodiment, and the present invention can also be applied in other embodiments.

[0109] For example, the differential device 64 of the above embodiment can function as a transmission with three or more gears or as a continuously variable transmission. The differential device 64 can also be configured using a plurality of planetary gear devices.

[0110] Further, in the transfer case 28 of the above embodiment, a TF clutch CF1, a TF brake BF1, a first engagement clutch D1, and a second engagement clutch D2 are provided. However, if only the torque separation mode is to be established, these TF clutch CF1, TF brake BF1, first engagement clutch D1, and second engagement clutch D2 can all be omitted, the first output shaft 66 can be connected to the TF input shaft 62, and the driving gear 70 can be connected to the ring gear R, etc. The structure of the transfer case 28 can be appropriately changed according to the type of driving mode. As long as a clutch is provided between the first output shaft 66 and the gear carrier CA and can be turned on and off, it is also possible to perform front-wheel drive (FF) type EV driving in which the power from the TF rotary machine MGF is transmitted from the second output shaft 72 to the front-wheel 14 side via the second engagement clutch D2 and drive, and clutches and brakes can be added as needed.

[0111] Further, it can also be configured such that the first output shaft 66 of the above embodiment is an output shaft for outputting the power from the first power source PU1 to the front-wheel 14, and the second output shaft 72 is an output shaft for outputting power to the rear-wheel 16.

[0112] In addition, in the above-described embodiment, the power transmission device 18 including the engine on-off clutch K0 and the rotary machine on-off clutch K2 is illustrated, but is not limited to this configuration. For example, either one or both of the engine on-off clutch K0 and the rotary machine on-off clutch K2 can be omitted.

[0113] In addition, in the above-described embodiment, the automatic transmission 50 may also be a synchronized engagement type parallel two-shaft automatic transmission including a known DCT (Dual Clutch Transmission) or a known belt-type continuously variable transmission or the like. An electric continuously variable transmission can also be employed.

[0114] In addition, in the above-described embodiment, the torque converter 48 is used as the fluid transmission device, but is not limited to this configuration. For example, as the fluid transmission device, another fluid transmission device such as a fluid coupling without torque amplification function can be used instead of the torque converter 48. By using a starting clutch and an electric continuously variable transmission, the fluid transmission device such as the torque converter 48 can also be omitted.

[0115] Although not illustrated one by one, the present invention can be implemented in a manner that various changes and improvements are made according to the knowledge of those skilled in the art.

Claims

1. A vehicle drive device (10) includes: a power source (PU1) having an engine (12) and a first rotating electric machine (MGM); a first output shaft (66) that inputs power from the power source (PU1) and outputs the power to one of a front wheel (14) and a rear wheel (16); a second output shaft (72) that outputs the power to the other of the front wheel (14) and the rear wheel (16); a power distribution device (28) that distributes a part of the power from the power source (PU1) input to the first output shaft (66) to the second output shaft (72); and a control device (130). The vehicle drive device (10) is characterized in that the power distribution device (28) includes a second rotating electric machine (MGF) and a differential device (64) having a first rotating element (S) to which the second rotating electric machine (MGF) is connected, a second rotating element (CA) to which the first output shaft (66) is connected, and a third rotating element (R) to which the second output shaft (72) is connected. The power distribution device (28) is configured to distribute a part of the power input to the first output shaft (66) from the power source (PU1) to the second output shaft (72) by applying a reaction force to the first rotating element (S) using the power generation torque of the second rotating electric machine (MGF). The control device (130) includes a torque separation control unit (142) that performs power generation control to control the power generation torque of the second rotating electric machine (MGF) so that a power distribution ratio (Rx) for the first output shaft (66) and the second output shaft (72) becomes a target distribution ratio (Rdis), and controls the total torque (Tpu1) of the power source (PU1) including the engine (12) and the first rotating electric machine (MGM) so as to obtain a required drive torque regardless of the power generation torque. The torque separation control unit (142) has a power consumption control unit (144) that supplies part or all of the power generation power obtained by the power generation control to the first rotating electric machine (MGM) to drive the first rotating electric machine (MGM) without passing through a power storage device (24) in such a manner that the operating state of the engine (12) approaches an optimal state of fuel economy.

2. The vehicle drive device (10) according to claim 1, characterized in that the torque separation control unit (142) includes a charge control unit (146) that charges all of the power generation power into the power storage device (24). The torque separation control unit (142) selects whether to perform control based on the charge control unit (146) or control based on the power consumption control unit (144) according to the operating state of the engine (12).

3. The vehicle drive device (10) according to claim 2, characterized in that The torque separation control unit (142) determines whether it is possible to drive the first rotating electric machine (MGM) by supplying part or all of the generated power to the first rotating electric machine (MGM), so that the operating state of the engine (12) approaches the optimal state of fuel economy. When it is possible to approach this optimal state of fuel economy, the control based on the power consumption control unit (144) is selected. When it is not possible to approach this optimal state of fuel economy, the control based on the charging control unit (146) is selected.

4. The vehicle drive device (10) according to claim 2 or 3, characterized in that the torque separation control unit (142) determines whether the state of charge value of the power storage device (24) exceeds a predetermined determination value (α). When it exceeds this determination value (α), the selection based on the operating state of the engine (12) is not performed, and all of the generated power is supplied to the first rotating electric machine (MGM) without passing through the power storage device (24) to drive the first rotating electric machine (MGM).

5. The vehicle drive device (10) according to any one of claims 1 to 3, characterized in that when it is possible to drive the first rotating electric machine (MGM) by supplying the generated power to the first rotating electric machine (MGM) so that the operating state of the engine (12) approaches the optimal state of fuel economy, and when a part of the generated power remains, the power consumption control unit (144) charges the remaining power (Wsur) to the power storage device (24).

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