Vehicle drive device

Abstract

The present application provides a vehicle drive device that suppresses deterioration of running stability at the time of switching of a drive mode in conjunction with switching of a power source. At the time of switching of the drive mode from a first drive mode to a second drive mode, after the first engagement device is switched from a slip state to an engaged state while the second engagement device is maintained in an engaged state, the power source is switched from a second power source to a first power source, so the power source is switched in a state in which the torque distribution ratio of the front wheels and the rear wheels is fixed. That is, a change in the torque distribution ratio caused by switching of the power source can be prevented. Therefore, at the time of switching of the drive mode in conjunction with switching of the power source, deterioration of running stability can be suppressed.

Description

Technical Field

[0001] The present invention relates to a vehicle drive device including a differential device for distributing torque to front wheels and rear wheels. Background Art

[0002] The following vehicle drive device is well known, comprising: a first power source; a first output rotating member that receives power from the first power source and outputs power to one of the front and rear wheels; a second output rotating member that outputs power to the other of the front and rear wheels; a second power source; a differential device having a first rotating element connected to the second power source, a second rotating element connected to one of the first and second output rotating members, and a third rotating element; a first engaging device that selectively connects the third rotating element to the other of the first and second output rotating members; a second engaging device that selectively connects any two of the first, second, and third rotating elements; and a control device. For example, the power transmission device described in Patent Document 1 is such a vehicle drive device.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-131153

[0006] In the aforementioned vehicle drive device, a first drive mode and a second drive mode can be established as drive modes for driving the vehicle. The first drive mode controls the first engaging device to a slipping state and maintains the second engaging device in an engaged state, while using power from the second power source to achieve an all-wheel drive state, controlling the torque distribution ratio between the front and rear wheels. The second drive mode maintains both the first and second engaging devices in an engaged state, maintaining the torque distribution ratio constant, while using power from the first power source to achieve an all-wheel drive state. Furthermore, when the first and second drive modes are established as drive modes as described above, the power source for driving the vehicle is switched between the second power source and the first power source as the drive mode is switched between the first and second drive modes. Therefore, the torque distribution ratio between the front and rear wheels may change as the power source is switched. This may lead to a deterioration in driving stability. Summary of the Invention

[0007] Problems to be solved by the invention

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle drive device capable of suppressing deterioration in driving stability when switching a drive mode accompanying switching of a power source.

[0009] Means for solving problems

[0010] and a second clutch mechanism that couples the first and second wheels to a first position and a second position to connect the first and second wheels, respectively. 10. The control device of claim 9, wherein the control device further comprises a first and a second driving mode, wherein the first driving mode controls the first engaging device to be in a slipping state and the second engaging device to be maintained in an engaged state, while the vehicle is put into an all-wheel drive state by the power from the second power source, and the torque distribution ratio between the front wheels and the rear wheels is controlled; the second driving mode controls the first and the second engaging devices to be in an engaged state and the torque distribution ratio is fixed, while the vehicle is put into an all-wheel drive state by the power from the first power source; and (c) when the driving mode is switched from the first driving mode to the second driving mode, after the first engaging device is switched from the slipping state to the engaged state while the second engaging device is maintained in the engaged state, the power source for driving the vehicle is switched from the second power source to the first power source.

[0011] Furthermore, according to the vehicle drive device described in the first invention, in the second invention, when the power source is switched from the second power source to the first power source, the control device reduces the torque of the second power source in accordance with the increase in the torque of the first power source.

[0012] 18. The swiftly and minutely adjusting device for a vehicle as claimed in claim 15, wherein the first and second gears are pivotally connected to each other with respect to each other, and the second gear is pivotally connected to the front wheel; the gear train is pivotally connected to the front wheel; and the like. and a control device, wherein (b) the control device is capable of establishing a first drive mode and a second drive mode as drive modes for driving the vehicle, wherein the first drive mode controls the first engaging device to be in a slipping state and maintains the second engaging device in an engaged state, while the vehicle is put into an all-wheel drive state by power from the second power source, and controls the torque distribution ratio between the front wheels and the rear wheels; the second drive mode maintains both the first engaging device and the second engaging device in an engaged state and fixes the torque distribution ratio, while the vehicle is put into an all-wheel drive state by power from the first power source; and (c) when the drive mode is switched from the second drive mode to the first drive mode, after the power source for driving the vehicle is switched from the first power source to the second power source, the second engaging device is maintained in the engaged state, while the first engaging device is switched from the engaged state to the slipping state.

[0013] Furthermore, according to the vehicle drive device described in the third invention, in a fourth invention, when the power source is switched from the first power source to the second power source, the control device reduces the torque of the first power source in accordance with the increase in the torque of the second power source.

[0014] Effects of the Invention

[0015] According to the first invention, when the drive mode is switched from the first drive mode to the second drive mode, the power source is switched from the second power source to the first power source after the first engagement device is switched from the slipping state to the engaged state while the second engagement device is maintained in the engaged state. This allows the power source to be switched while the torque distribution ratio between the front and rear wheels is fixed. This prevents changes in the torque distribution ratio caused by the power source switch. Consequently, a deterioration in driving stability can be suppressed during the drive mode switch associated with the power source switch.

[0016] Furthermore, according to the second invention, when the power source is switched from the second power source to the first power source, the torque of the second power source is reduced according to the increase in the torque of the first power source, thereby suppressing the decrease in driving torque accompanying the switching of the power source.

[0017] Furthermore, according to the third invention, when the drive mode is switched from the second drive mode to the first drive mode, after the power source is switched from the first power source to the second power source, the second engaging device is maintained in the engaged state while the first engaging device is switched from the engaged state to the slipping state. This allows the power source to be switched while the torque distribution ratio between the front and rear wheels is fixed. This prevents changes in the torque distribution ratio caused by the power source switch. Consequently, it is possible to suppress deterioration in driving stability when switching the drive mode accompanied by the power source switch.

[0018] Furthermore, according to the fourth invention, when the power source is switched from the first power source to the second power source, the torque of the first power source is reduced as the torque of the second power source increases, thereby suppressing the decrease in driving torque accompanying the switching of the power source. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a diagram illustrating a schematic configuration of a vehicle drive device to which the present invention is applied, and is a diagram illustrating control functions for various controls in the vehicle drive device and a main portion of a control system.

[0020] Figure 2 It is an explanation Figure 1 A diagram schematically illustrates the structure of a hybrid transmission.

[0021] Figure 3 It is an explanation Figure 2 An operation engagement table showing the relationship between the speed shifting operation of the automatic transmission and the operation of the engagement device used for the speed shifting operation of the automatic transmission.

[0022] Figure 4 It is an explanation Figure 1 Diagram of the schematic structure of the transfer case.

[0023] Figure 5 It shows Figure 4 A nomogram showing the relative relationship between the rotational speeds of the various rotating elements in the transfer case.

[0024] Figure 6 It means Figure 4 An operation engagement table showing the relationship between each mode established in the transfer case and the control state of each engagement device in the transfer case.

[0025] Figure 7 This is a diagram showing an example of an AT gear stage shift map used for shift control of an automatic transmission and a drive range switching map used for drive mode switching control, and also shows the relationship between them.

[0026] Figure 8 This is a diagram explaining that the operating point of the engine can be changed according to the torque of the rotating machine.

[0027] Figure 9 This is a flowchart illustrating a main portion of the control operation of the electronic control device, and is a flowchart illustrating the control operation for suppressing deterioration of driving stability when switching the drive mode accompanying switching of the power source.

[0028] Figure 10 This is a flowchart illustrating the main part of the control operation of the electronic control device, and is a flowchart illustrating the control operation for suppressing the deterioration of driving stability when the drive mode is switched with the switching of the power source. Figure 9 Flowcharts of different embodiments.

[0029] Figure 11 This is a diagram illustrating a schematic structure of a transfer case according to another embodiment of the present invention. Figure 4 Different embodiments of transfer cases.

[0030] Figure 12 It shows Figure 11 A nomogram showing the relative relationship between the rotational speeds of the various rotating elements in the transfer case.

[0031] Figure 13 It means Figure 11 An operation engagement table showing the relationship between each mode established in the transfer case and the control state of each engagement device in the transfer case.

[0032] Figure 14 This is a diagram illustrating a schematic structure of a transfer case according to another embodiment of the present invention. Figure 4 Different embodiments of transfer cases.

[0033] Figure 15 It shows Figure 14 A nomogram showing the relative relationship between the rotational speeds of the various rotating elements in the transfer case.

[0034] Figure 16 It means Figure 14 An operation engagement table showing the relationship between each mode established in the transfer case and the control state of each engagement device in the transfer case.

[0035] Figure 17 This is a diagram illustrating a schematic structure of a transfer case according to another embodiment of the present invention. Figure 4 Different embodiments of transfer cases.

[0036] Figure 18 It shows Figure 17 A nomogram showing the relative relationship between the rotational speeds of the various rotating elements in the transfer case.

[0037] Figure 19 It means Figure 17 An operation engagement table showing the relationship between each mode established in the transfer case and the control state of each engagement device in the transfer case.

[0038] Description of Reference Numerals

[0039] 8: Vehicles

[0040] 10: Vehicle drive device

[0041] 14: Front wheel

[0042] 16: Rear wheel

[0043] 64, 206, 306, 406: Differential gear

[0044] 66, 208, 302, 402: First output shaft (first output rotating member)

[0045] 74, 212, 304, 404: Second output shaft (second output rotating member)

[0046] 130: Electronic control unit (control unit)

[0047] CD1: Switching clutch (first engagement device)

[0048] CF1: TF clutch (second engagement device)

[0049] PU1: First Power Source

[0050] PU2: Second power source

[0051] RE1: First rotating element

[0052] RE2: Second rotating element

[0053] RE3: Third Rotating Element DETAILED DESCRIPTION

[0054] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0055] [Example 1]

[0056] Figure 1 1 is a diagram illustrating a schematic configuration of a vehicle drive device 10 provided in a vehicle 8 to which the present invention is applied, and is a diagram illustrating a main portion of a control function and a control system for various controls in the vehicle drive device 10. Figure 1 In the figure, the vehicle drive device 10 includes an engine 12 (see "ENG" in the figure), a TM rotating machine MGM, and a TF rotating machine MGF, which function as a power source. Vehicle 8 is a hybrid vehicle. Furthermore, 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 other components to the front wheels 14 and rear wheels 16, respectively. The engine 12, the TM rotating machine MGM, and the TF rotating machine MGF are referred to as the power source PU unless otherwise specified. In particular, the engine 12 and the TM rotating machine MGM, which output power to the torque converter 48 and automatic transmission 50 described later, are the first power source PU1. The TM rotating machine MGM included in the first power source PU1 is the first rotating machine. Furthermore, the TF rotating machine MGF included in the transfer case 28 described later is the second rotating machine and is the second power source PU2 that serves as a power source for driving the vehicle 8, either in place of or in addition to the first power source PU1.

[0057] Vehicle 8 is an all-wheel drive vehicle capable of distributing a portion of the torque transmitted to rear wheels 16 by vehicle drive device 10 to front wheels 14. In addition to rear-wheel drive, in which torque is transmitted only to rear wheels 16, vehicle drive device 10 is also capable of front-wheel drive, in which torque is transmitted only to front wheels 14. Vehicle 8 is a four-wheel drive vehicle, having two front wheels 14 and two rear wheels 16, that is, a vehicle having four wheels. In this embodiment, all-wheel drive (AWD) is synonymous with four-wheel drive (4WD). Rear-wheel drive and front-wheel drive are two-wheel drive (2WD), respectively.

[0058] The engine 12 is a well-known internal combustion engine such as a gasoline engine or a diesel engine. The engine 12 is controlled by an electronic control unit 130 (described later) controlling an engine control unit 20 including a throttle actuator, a fuel injection device, an ignition device, and the like included in the vehicle drive device 10. This controls the torque of the engine 12, i.e., the engine torque Te.

[0059] The TM rotating machine MGM and the TF rotating machine MGF are rotating electrical machines that function as both a motor that generates mechanical power from electrical power and a generator that generates electrical power from mechanical power, respectively. They are so-called motor generators. The TM rotating machine MGM and the TF rotating machine MGF are each connected to a battery 24 included in the vehicle drive device 10 via an inverter 22 included in the vehicle drive device 10. The TM rotating machine MGM and the TF rotating machine MGF control the inverter 22 using an electronic control unit 130 (described later) to control the torque of the TM rotating machine MGM, i.e., the MGM torque Tmgm, and the torque of the TF rotating machine MGF, i.e., the MGF torque Tmgf. The MGM torque Tmgm and the MGF torque Tmgf, respectively, become power running torque (also synonymous with motor torque) when the rotating machine functions as a motor, and regenerative torque (also synonymous with power generation torque) when the rotating machine functions as a generator. The battery 24 is a power storage device that transfers power to and from the TM rotating machine MGM and the TF rotating machine MGF. The term "electric power" is also synonymous with electric energy unless otherwise specified. The term "power" is also synonymous with driving force, torque, and force unless otherwise specified.

[0060] The power transmission device 18 includes a hybrid transmission 26 (see "HEV T / M" in the figure), a transfer case 28 (see "T / F" in the figure), a front propeller shaft 30, a rear propeller shaft 32, a front differential 34 (see "FDiff" in the figure), a rear differential 36 (see "RDiff" in the figure), 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 from the first power source PU1, which has been transmitted via the hybrid transmission 26, is transmitted from the transfer case 28 to the rear wheels 16 in sequence via the rear propeller shaft 32, the rear differential 36, the rear drive shaft 40, and the like. Furthermore, in the power transmission device 18, when a portion of the torque from the first power source PU1 transmitted to the transfer case 28 is distributed to the front wheels 14, the distributed torque is transmitted to the front wheels 14 in sequence via the front propeller shaft 30, the front differential 34, the front drive shaft 38, and the like.

[0061] The hybrid transmission 26 includes a transmission case 42 as a stationary member (non-rotating member). The transfer case 28 includes a transfer case 44 as a stationary member (non-rotating member) connected to the transmission case 42. The TM rotating machine MGM is disposed within the transmission case 42. The TF rotating machine MGF is disposed within the transfer case 44.

[0062] Figure 2 1 is a diagram illustrating a schematic structure of the hybrid transmission 26. Figure 2In the embodiment, the hybrid transmission 26 includes a rotary machine connecting shaft 46, a torque converter 48, and an automatic transmission 50 disposed on a common rotation axis CL1 within a transmission case 42. The torque converter 48 and the automatic transmission 50 are configured to be substantially symmetrical with respect to the rotation axis CL1. Figure 2 The lower half is omitted relative to the rotation axis CL1. The rotation axis CL1 is the axis of the crankshaft of the engine 12, the rotating machine connecting shaft 46 connected to the crankshaft, the transmission input shaft 52 as the input rotating element of the automatic transmission 50, and the transmission output shaft 54 ​​as the output rotating element of the automatic transmission 50.

[0063] The rotating machine connecting shaft 46 connects the engine 12 to the torque converter 48. The TM rotating machine MGM is connected to the rotating machine connecting shaft 46 in a power-transmitting manner. The torque converter 48 includes a pump impeller 48a connected to the rotating 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 is an input-side rotating element connected to the first power source PU1 in a power-transmitting manner. The turbine impeller 48b is the output member of the torque converter 48 and is an output-side rotating element connected to the automatic transmission 50 in a power-transmitting manner. The rotating machine connecting shaft 46 is also the input rotating member of the torque converter 48. The transmission input shaft 52 is also the output rotating member of the torque converter 48, formed integrally with the turbine shaft, which is rotationally driven by the turbine impeller 48b. The torque converter 48 is a fluid transmission device that transmits power from the first power source PU1 to the transmission input shaft 52 via a fluid. The torque converter 48 includes a lockup clutch LU as a direct connection clutch that connects the pump impeller 48 a and the turbine impeller 48 b .

[0064] The automatic transmission 50 is provided 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 power from the first power source PU1 to the transfer case 28. Thus, the torque converter 48 and the automatic transmission 50 each transmit power from the first power source PU1 to the transfer case 28.

[0065] Automatic transmission 50 is a well-known planetary gear type automatic transmission that includes, for example, a plurality of planetary gear sets, namely a first planetary gear set 56 and a second planetary gear set 58, and a plurality of engagement devices, namely, clutch C1 including a one-way clutch F1, clutch C2, brake B1, and brake B2. Hereinafter, clutch C1, clutch C2, brake B1, and brake B2 will be referred to as engagement devices CB unless otherwise specified.

[0066] The engagement device CB is a well-known hydraulic friction engagement device composed of a multi-plate or single-plate clutch pressed by a hydraulic actuator, a brake, a band brake tightened by a hydraulic actuator, etc. The engagement device CB is operated by utilizing the hydraulic control circuit 60 (see FIG. Figure 1 The regulated hydraulic pressures of the engagement device CB, namely the CB hydraulic pressures PRcb, supplied by the hydraulic pressure regulator, vary the torque capacities, namely the CB torques Tcb, thereby switching operating states (i.e., control states) such as the engaged state, the slip state, and the released state. The hydraulic control circuit 60 is controlled by the electronic control unit 130, described later.

[0067] In the automatic transmission 50, the rotating elements of the first planetary gear set 56 and the second planetary gear set 58 are directly connected to each other or partially connected to each other indirectly via the engagement device CB or the one-way clutch F1, or are connected to the transmission input shaft 52, the transfer case 42, or the transmission output shaft 54. The rotating elements of the first planetary gear set 56 are the sun gear S1, the carrier CA1, and the ring gear R1, and the rotating elements of the second planetary gear set 58 are the sun gear S2, the carrier CA2, and the ring gear R2.

[0068] The automatic transmission 50 is a stepped transmission that establishes any of a plurality of shift speeds (also called gear stages) with different speed ratios (also called gear ratios) γat (=AT input speed Ni / AT output speed No) by engaging any of the engagement devices CB. The automatic transmission 50 switches gear stages in response to the driver's (=driver's) accelerator operation, vehicle speed V, and other factors using the electronic control unit 130, described later. In this embodiment, the gear stages established by the automatic transmission 50 are referred to as AT gear stages. The AT input speed Ni is the speed of the transmission input shaft 52, the input speed of the automatic transmission 50, and is the same value as the turbine speed Nt, the speed of the turbine shaft rotationally driven by the turbine impeller 48b. The AT output speed No is the speed of the transmission output shaft 54, the output speed of the automatic transmission 50.

[0069] For example, Figure 3 As shown in the operation engagement table, the automatic transmission 50 is formed as a plurality of AT gears, with four forward AT gears being formed: AT1st speed gear ("1st" in the figure) through AT4th speed gear ("4th" in the figure). The AT1st speed gear has the highest speed ratio γat, and the speed ratio γat decreases as the AT gear becomes higher, which is the AT4th speed gear. Figure 3 The working engagement table summarizes the relationship between each AT gear and each control state of the engagement device CB. Figure 3In the figure, "○" indicates engagement, "△" indicates engagement during engine braking and coasting downshift of the automatic transmission 50, and a blank indicates release. When the AT gear stage is formed in the automatic transmission 50, the automatic transmission 50 becomes a state capable of transmitting power, that is, a state capable of transmitting power. The neutral state of the automatic transmission 50 ("N" in the figure) is a state in which the automatic transmission 50 cannot transmit power, that is, a state in which power cannot be transmitted, and is achieved, for example, by setting all the engagement devices CB to a released state and cutting off the power transmission in the automatic transmission 50. In addition, the automatic transmission 50 is set to a neutral state ("Rev" in the figure) when the vehicle 8 is traveling in reverse. When the vehicle 8 is traveling in reverse, power is output from the TF rotating machine MGF, for example.

[0070] Figure 4 : This is a diagram illustrating the schematic structure of the transfer case 28. The transfer case 28 includes a TF input shaft 62, a differential device 64, a TF clutch CF1, a TF brake BF1, a switching clutch CD1, a first output shaft 66, and a first sprocket 68, etc., which are arranged on a common rotation axis CL1, in the transfer case 44. In addition, the transfer case 28 includes a TF rotating machine MGF and a chain 70, etc., in the transfer case 44. In addition, the transfer case 28 includes a second sprocket 72 and a second output shaft 74, etc., which are arranged on a common rotation axis CL2, in the transfer case 44. The TF rotating machine MGF, the differential device 64, the TF clutch CF1, the TF brake BF1, the switching clutch CD1, and the first sprocket 68 are constructed to be roughly symmetrical with respect to the rotation axis CL1. Figure 4 The second sprocket 72 is configured to be substantially symmetrical with respect to the rotation axis CL2. Figure 4 The upper half of the figure is omitted relative to the rotation axis CL2 . The rotation axis CL2 is the axis of the second output shaft 74 , the front propeller shaft 30 , and the like.

[0071] The chain 70 is wound between the first sprocket 68 and the second sprocket 72 to connect them. In other words, the first sprocket 68 and the second sprocket 72 are connected via the chain 70 in a power-transmittable manner.

[0072] The TF clutch CF1, TF brake BF1, and switching clutch CD1 are each known wet hydraulic friction engagement devices comprised of multi-plate or single-plate engagement devices pressed by a hydraulic actuator. The TF clutch CF1 switches its control state by varying its torque capacity, or CF1 torque Tcf1, using the regulated hydraulic pressure of the TF clutch CF1, or CF1 hydraulic pressure PRcf1, supplied from the hydraulic control circuit 60. The control states of the TF clutch CF1 include a released state (also synonymous with the "completely released state"), in which the TF clutch CF1 is completely released; a slipping state (also synonymous with the "slip engaged state"), in which the TF clutch CF1 is engaged with slip; and an engaged state (also synonymous with the "completely engaged state"), in which the TF clutch CF1 is completely engaged. Similar to the TF clutch CF1, the TF brake BF1 also switches between controlled states such as the engaged state and the released state by varying the BF1 torque Tbf1 using the BF1 hydraulic pressure PRbf1 supplied from the hydraulic control circuit 60. Similar to the TF clutch CF1, the switching clutch CD1 also switches between controlled states such as the engaged state and the released state by varying the CD1 torque Tcd1 using the CD1 hydraulic pressure PRcd1 supplied from the hydraulic control circuit 60.

[0073] The TF input shaft 62 is connected to the transmission output shaft 54 ​​in a manner that can transmit power. The first output shaft 66 is connected to the rear propeller shaft 32 in a manner that can transmit power. The TF input shaft 62 and the first output shaft 66 are connected integrally. Thus, the power from the first power source PU1 is input to the first output shaft 66 via the automatic transmission 50, etc. In addition, the power input to the first output shaft 66 is transmitted to the rear wheel 16 via the rear propeller shaft 32, etc. The first output shaft 66 is a first output rotating member that is input with power from the first power source PU1 and outputs power to the rear wheel 16, which is one of the front wheels 14 and the rear wheels 16. It should be noted that the TF input shaft 62 and the first output shaft 66 can also be a single rotating shaft.

[0074] The second output shaft 74 is connected to the front propeller shaft 30 in a power-transmittable manner. Thus, power input to the second output shaft 74 is transmitted to the front wheel 14 via the front propeller shaft 30 and other means. The second output shaft 74 is a second output rotating member that outputs power to the front wheel 14, which is the other of the front wheel 14 and the rear wheel 16. The second sprocket 72 is fixed to the second output shaft 74 in a relatively non-rotatable manner.

[0075] The differential device 64 is comprised of a single-pinion planetary gear system, comprising a sun gear S, a carrier CA, and a ring gear R. The TF rotating machine MGF is connected to the sun gear S in a power-transmittable manner. The carrier CA is connected to the first sprocket 68. Therefore, the second output shaft 74 is connected to the carrier CA in a power-transmittable manner via the first sprocket 68, the chain 70, and the second sprocket 72. The ring gear R is selectively connected to the transfer case 44 via the TF brake BF1. Furthermore, the ring gear R is selectively connected to the TF input shaft 62 and the first output shaft 66 via the switching clutch CD1. Therefore, when the switching clutch CD1 is engaged or slipping, a portion of the power from the TF input shaft 62, or the first output shaft 66, is input to the ring gear R of the differential device 64. The sun gear S and the carrier CA are selectively connected via the TF clutch CF1. The TF clutch CF1 is an engaging device that selectively connects the sun gear S and the carrier CA. The TF brake BF1 is an engagement device that selectively connects the ring gear R and the transfer case 44 .

[0076] Figure 5 is a collinear diagram showing the relative relationship between the rotational speeds of the various rotating elements in the transfer case 28. Figure 5 In the figure, the three vertical lines Y1, Y2, and Y3 corresponding to the three rotating elements of the differential device 64 constituting the transfer case 28 are axes that, from the left, represent 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 vertical line Y0 shown to the left of the vertical line Y1 is an axis that represents the rotational speeds of the TF input shaft 62 and the first output shaft 66 corresponding to the input and output rotating element RE10.

[0077] If you use Figure 5 , in the transfer case 28, the input / output rotating element RE10 is selectively connected to the ring gear R via the switching clutch CD1 and is also connected to the rear propeller shaft 32. Furthermore, the input / output rotating element RE10 is connected to the first power source PU1 including the engine 12 via the hybrid transmission 26 in a power-transmittable manner.

[0078] In the differential device 64, the first rotating element RE1 is connected to the TF rotating machine MGF in a power-transmittable manner. The second rotating element RE2 is connected to the second output shaft 74, which is an output rotating element between the first output shaft 66 and the second output shaft 74. The third rotating element RE3 is selectively connected to the first output shaft 66 via the switching clutch CD1 and is selectively connected to the transfer case 44 via the TF brake BF1. The switching clutch CD1 is a first engagement device that selectively connects the third rotating element RE3 to the first output shaft 66, which is an output rotating element between the first output shaft 66 and the second output shaft 74. The first rotating element RE1 and the second rotating element RE2 are selectively connected via the TF clutch CF1. The TF clutch CF1 is a second engagement device that selectively connects any two rotating elements among the first rotating element RE1, the second rotating element RE2, and the third rotating element RE3. 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.

[0079] In the differential device 64, when the TF clutch CF1 is engaged and the TF brake BF1 is released, the first, second, and third rotating elements RE1, RE2, and 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, the rotational speed of the second rotating element RE2 is reduced relative to the rotational speed of the first rotating element RE1. Therefore, by adding the TF clutch CF1 and the TF brake BF1, the differential device 64 functions as a transmission device that selectively establishes a high gear speed when the TF clutch CF1 is engaged and a low gear speed when the TF brake BF1 is engaged.

[0080] Furthermore, when both the TF clutch CF1 and the TF brake BF1 are released, the differential device 64 can perform a differential action. Thus, the differential device 64 functions as a center differential. In the transfer case 28, when the switching clutch CD1 is engaged or slipping, the differential device 64 can use the reaction torque of the TF rotating machine MGF coupled to the first rotating element RE1 to distribute the torque from the first power source PU1, which is input to the third rotating element RE3, to the second rotating element RE2. Alternatively, instead of allowing the reaction torque of the TF rotating machine MGF to act, the differential device 64 can limit the differential action by setting the TF clutch CF1 to a slipping or engaged state, thereby distributing the torque from the first power source PU1, which is input to the third rotating element RE3, to the second rotating element RE2. Thus, the transfer case 28 functions as a torque distribution device that distributes a portion of the torque from the first power source PU1, which is input to the first output shaft 66, to the second output shaft 74. As a result, the transfer case 28 can distribute the torque to the front wheels 14 and the rear wheels 16 .

[0081] Figure 6 2 is an operation engagement table that explains the relationship between each mode established in the transfer case 28 and the control state of each engagement device in the transfer case 28. Figure 6 In the figure, “○” indicates engagement, a blank indicates release, and “○ sliding control” indicates that the corresponding engagement device is controlled to a sliding state, that is, is sliding controlled.

[0082] The "BEV(FF) High" mode (also referred to as m1 mode) and the "BEV(FF) Low" mode (also referred to as m2 mode) designated m1 are achieved by engaging either the TF clutch CF1 or the TF brake BF1 and releasing the switching clutch CD1. The m1 and m2 modes are modes in which power from the TF rotating machine MGF is transmitted to the front wheels 14 in the differential device 64, which is in a high gear position based on the engagement of the TF clutch CF1 or a low gear position based on the engagement of the TF brake BF1. The m1 and m2 modes are motor drive modes (BEV drive modes) that enable motor travel (BEV travel) using only the TF rotating machine MGF as the power source, for example, while the first power source PU1 is stopped. BEV travel in both the m1 and m2 modes is achieved through front-wheel drive.

[0083] The "BEV_LSD" mode, designated m3 (also referred to as m3 mode), is achieved by engaging the TF clutch CF1, releasing the TF brake BF1, and performing slip control on the switching clutch CD1. m3 mode is also a BEV drive mode. In m3 mode, the differential device 64 distributes the torque of the TF rotating machine MGF to the front wheels 14 and rear wheels 16 at a desired arbitrary ratio corresponding to the torque capacity of the switching clutch CD1, while operating in a state equivalent to a high gear stage. In other words, in m3 mode, by adjusting the torque capacity of the switching clutch CD1 in the BEV drive mode, AWD driving is possible, in which the torque distribution ratio Rx can be arbitrarily changed.

[0084] The torque distribution ratio Rx is the ratio of the torque from the power source PU distributed to the front wheels 14 and the rear wheels 16. The torque distribution ratio Rx can be expressed, for example, as the ratio of the torque transmitted from the power source PU to the rear wheels 16 relative to the total torque transmitted from the power source PU to the rear wheels 16 and the front wheels 14, that is, the rear-wheel distribution ratio Xr. Alternatively, the torque distribution ratio Rx can be expressed, for example, as the ratio of the torque transmitted from the power source PU to the front wheels 14 relative to the total torque transmitted from the power source PU to the rear wheels 16 and the front wheels 14, that is, the front-wheel distribution ratio Xf (=1-Xr).

[0085] The "BEV_Lock" mode, designated m4 (also referred to as m4 mode), is achieved by engaging the TF clutch CF1, releasing the TF brake BF1, and engaging the switching clutch CD1. m4 mode is also a BEV drive mode. m4 mode distributes the torque of the TF rotating machine MGF to the front wheels 14 and rear wheels 16 at a fixed ratio by placing the differential device 64 in the differential lock state. In other words, in m4 mode, AWD driving is possible with the torque distribution ratio Rx fixed at, for example, 50% in the BEV drive mode.

[0086] In each of the BEV drive modes of the m1 mode, the m2 mode, the m3 mode, and the m4 mode, for example, by placing the automatic transmission 50 in the neutral state, the drag of the stopped engine 12 can be eliminated.

[0087] The "first power source torque distribution" mode numbered m5 (also referred to as the m5 mode) is implemented by making the TF clutch CF1 and the TF brake BF1 both into the released state, and making the switching clutch CD1 into the engaged state. The m5 mode is a mode in which, for example, the differential 64 is in a state equivalent to the high gear range, and torque from the first power source PU1 transmitted from the first output shaft 66 to the ring gear R of the differential 64 via the switching clutch CD1 is borne by the sun gear S using the reaction torque of the TF rotary machine MGF, so that the torque of the first power source PU1 is distributed to the front wheels 14 and the rear wheels 16 at a desired arbitrary ratio corresponding to the reaction torque of the TF rotary machine MGF. In the m5 mode in the transfer 28, the TF rotary machine MGF is caused to perform power running. The m5 mode is, for example, a hybrid drive mode, i.e., an HEV drive mode, in which engine running, i.e., hybrid running (= HEV running), in which at least the first power source PU1 (particularly, the engine 12) is used as a power source to travel, is possible. That is, in the m5 mode, by controlling the torque of the TF rotary machine MGF in the HEV drive mode, AWD running in which the torque distribution ratio Rx can be arbitrarily changed is possible.

[0088] The "first power source LSD" mode numbered m6 (also referred to as the m6 mode) is implemented by performing slip control on the TF clutch CF1 and making the TF brake BF1 into the released state, and making the switching clutch CD1 into the engaged state. The m6 mode is also an HEV drive mode. The m6 mode is a mode in which, for example, the differential 64 is in a state equivalent to the high gear range, and torque of the first power source PU1 is distributed to the front wheels 14 and the rear wheels 16 at a desired arbitrary ratio corresponding to the torque capacity of the TF clutch CF1 by restriction of the differential action of the differential 64 based on the slip state of the TF clutch CF1. That is, in the m6 mode, by adjusting the torque capacity of the TF clutch CF1 in the HEV drive mode, AWD running in which the torque distribution ratio Rx can be arbitrarily changed is possible. In the m6 mode, power from the TF rotary machine MGF can be applied to the drive torque Tr.

[0089] The "First Power Source Lock" mode, numbered m7 (also referred to as m7 mode), is achieved by engaging the TF clutch CF1, releasing the TF brake BF1, and engaging the switching clutch CD1. m7 mode is also an HEV drive mode. m7 mode distributes torque from the first power source PU1 to the front wheels 14 and rear wheels 16 at a fixed ratio by locking the differential device 64. In other words, in m7 mode, AWD driving is possible in the HEV drive mode, with the torque distribution ratio Rx fixed at, for example, 50%. In m7 mode, power from the TF rotating machine MGF can be applied to the drive torque Tr.

[0090] The "First Power Source Two-Wheel Drive (FR)" mode, designated m8 (also referred to as m8 mode), is achieved by releasing the TF clutch CF1, TF brake BF1, and switching clutch CD1. m8 mode is also an HEV drive mode. m8 mode enables rear-wheel drive using only power from the first power source PU1.

[0091] In addition, for example, by operating the first power source PU1 and putting the automatic transmission 50 into a power transmission state under the control states of each engagement device in the transfer case 28 that are respectively equivalent to the m1 mode, m2 mode and m3 mode, other modes that allow AWD driving in the HEV drive mode can be established.

[0092] Return to Figure 1 The vehicle drive device 10 includes a mechanical oil pump, namely a mechanical oil pump 80, an electric oil pump, namely an electric oil pump 82, and a pump motor 84. The mechanical oil pump 80 is connected to the rotary machine connecting shaft 46 (see Figure 2 ), driven by the first power source PU1 to discharge the hydraulic oil OIL used in the power transmission device 18. The pump motor 84 is a motor dedicated to the electric oil pump 82, driving the electric oil pump 82. The electric oil pump 82 is driven by the pump motor 84 to discharge the hydraulic oil OIL. The hydraulic oil OIL discharged by the mechanical oil pump 80 and the electric oil pump 82 is supplied to the hydraulic control circuit 60. The hydraulic control circuit 60 supplies the CB hydraulic pressure PRcb, CF1 hydraulic pressure PRcf1, BF1 hydraulic pressure PRbf1, CD1 hydraulic pressure PRcd1, etc., each pressure-regulated based on the hydraulic oil OIL discharged from at least one of the mechanical oil pump 80 and the electric oil pump 82.

[0093] The vehicle drive device 10 includes an electronic control unit 130 as a controller including a control device for controlling the power source PU, the transfer case 28 , and the like. Figure 1This figure shows the input / output system of the electronic control unit 130 and is a functional block diagram illustrating the main components of the control functions of the electronic control unit 130. The electronic control unit 130 is configured, for example, as a so-called microcomputer including a CPU, RAM, ROM, and input / output interfaces. The CPU utilizes the RAM's temporary storage function and processes signals according to programs pre-stored in the ROM to execute various controls on the vehicle drive device 10. The electronic control unit 130 is configured to include various computers for engine control, transmission control, and the like, as needed.

[0094] Various signals based on detection values ​​of various sensors provided in the vehicle drive device 10 (e.g., the engine speed sensor 90, the MGM speed sensor 92, the turbine speed sensor 94, the AT output speed sensor 96, the vehicle speed sensor 98, the MGF speed sensor 100, the accelerator opening sensor 102, the throttle opening sensor 104, the brake pedal sensor 106, the gear position sensor 108, the acceleration sensor 110, the yaw rate sensor 112, the steering sensor 114, the battery sensor 116, the oil temperature sensor 118, the differential lock selection switch 120, etc.) are supplied to the electronic control unit 130 (e.g., the engine speed Ne of the engine 12, the MGM speed Nmgm of the TM rotating machine MGM, the turbine speed Nt having the same value as the AT input speed Ni, the AT output speed No, the TF output speed Nof of the first output shaft 66 corresponding to the vehicle speed V, the TF rotating machine MGM, etc.). The rotation speed of the engine MGF, i.e., the MGF rotation speed Nmgf; the driver's accelerator operation amount indicating the size of the driver's acceleration operation, i.e., the accelerator opening θacc; the opening of the electronic throttle, i.e., the throttle opening θth; the brake-on signal Bon, which is a signal indicating the state of the brake pedal for operating the wheel brake by the driver; the shift operation position POSsh, which is an operation position of the shift lever of the vehicle 8; the longitudinal acceleration Gx and the left and right acceleration Gy of the vehicle 8; the angular velocity of rotation of the vehicle 8 around the vertical axis, i.e., the yaw rate Ryaw; the steering angle θsw and the steering direction Dsw of the steering wheel of the vehicle 8; the battery temperature THbat of the battery 24; the battery charge and discharge current Ibat; the battery voltage Vbat; the temperature of the working oil OIL, i.e., the working oil temperature THoil; the lock mode on signal LOCKon, which is a signal indicating that the "BEV_Lock" mode or the "first power source Lock" mode has been selected by the driver, etc.).

[0095] The differential lock selection switch 120 is provided, for example, near a driver's seat. The differential lock selection switch 120 is a switch that is turned on by the driver when the differential device 64 in the transfer case 28 is set to the differential lock state.

[0096] Various command signals (e.g., an engine control command signal Se for controlling the engine 12, an MGM control command signal Smgm for controlling the TM rotating machine MGM, an MGF control command signal Smgf for controlling the TF rotating machine MGF, a hydraulic 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 control command signal Scbf for controlling the respective control states of the TF clutch CF1, the TF brake BF1, and the switching clutch CD1 related to the control of the transfer case 28, an electric oil pump control command signal Seop for controlling the electric oil pump 82, a brake control command signal Sb for controlling the braking force generated by the wheel brakes, an information reporting control command signal Sinf for reporting various information to the driver, etc.) are output from the electronic control unit 130 to each device of the vehicle 8 (e.g., the engine control unit 20, the inverter 22, the hydraulic control circuit 60, the pump motor 84, the wheel brake device 122, the information reporting device 124, etc.).

[0097] To implement various controls in the vehicle drive device 10 , the electronic control unit 130 includes an AT shift control unit 132 serving as an AT shift control means, a hybrid control unit 134 serving as a hybrid control means, and a drive state control unit 136 serving as a drive state control means.

[0098] The AT speed change control unit 132 uses, for example, Figure 7 The AT gear shift map shown in the figure determines the shifting of the automatic transmission 50 and outputs a hydraulic control command signal Sat to the hydraulic control circuit 60, as needed, for executing the shifting control of the automatic transmission 50. The AT gear shift map is a relationship previously determined and stored through experimentation or design. For example, the AT gear shift map includes predetermined shift lines for determining the shifting of the automatic transmission 50 on a two-dimensional coordinate system with vehicle speed V and required drive torque Trdem as variables. The AT gear shift map may use an AT output speed No, etc., instead of vehicle speed V. Alternatively, the required drive force Frdem, accelerator opening θacc, throttle opening θth, etc., may be used instead of required drive torque Trdem. The shift lines in the AT gear shift map are an upshift line for determining an upshift, as shown by the solid line, and a downshift line for determining a downshift, as shown by the dashed line.

[0099] The hybrid control unit 134 includes the functions of an engine control unit 134a, which serves as an engine control unit for controlling the operation of the engine 12, and a rotating machine control unit 134b, which serves as a rotating machine control unit for controlling the operation of the TM rotating machine MGM and the TF rotating machine MGF via the inverter 22. These control functions are used to perform hybrid drive control based on the engine 12, the TM rotating machine MGM and the TF rotating machine MGF.

[0100] The hybrid control unit 134 calculates the driver's drive demand for the vehicle 8 by applying the accelerator opening θacc and the vehicle speed V to a predetermined relationship, such as a drive demand map. The drive demand is, for example, the required drive torque Trdem [Nm] at the drive wheels (front wheels 14 and rear wheels 16). Alternatively, the required drive force Frdem [N] at the drive wheels, the required drive power Prdem [W] at the drive wheels, or the required AT output torque at the transmission output shaft 54 ​​can be used as the drive demand. In other words, the required drive torque Trdem is the required drive power Prdem at the vehicle speed V at the time of command output. In calculating the drive demand, the TF output speed Nof, etc., may be used instead of the vehicle speed V.

[0101] 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 to achieve the required drive power Prdem, taking into account transmission loss, auxiliary load, the speed ratio γat of the automatic transmission 50, the gear stage of the differential device 64, the chargeable power Win and dischargeable power Wout of the battery 24, and other factors. The engine control command signal Se is, for example, a command value for the required engine power Pedem, which is a required value for achieving the engine torque Te at the engine speed Ne when the command is output. The engine power Pe is the output [W], or power, of the engine 12. The MGM control command signal Smgm is, for example, a command value for the power consumption Wcmgm or generated power Wgmgm of the TM rotating machine MGM, which is an MGM torque Tmgm at the MGM speed Nmgm when the command is output. The MGF control command signal Smgf is, for example, a command value for the power consumption Wcmgf or generated power Wgmgf of the TF rotating machine MGF, which is an MGF torque Tmgf at the MGF speed Nmgf when the command is output.

[0102] The chargeable power Win of the battery 24 is the maximum power that can be input, which limits the input power of the battery 24 and indicates the input limit of the battery 24. The dischargeable power Wout of the battery 24 is the maximum power that can be output, which limits the output power of the battery 24 and indicates the output limit of the battery 24. The chargeable power Win and the dischargeable power Wout of the 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 battery 24. The state of charge value SOC of the battery 24 is a value indicating the state of charge corresponding to the charge amount of the 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.

[0103] When the required drive power Prdem is in the motor drive range below a predetermined threshold, hybrid control unit 134 establishes the BEV drive mode as the drive mode for driving vehicle 8. On the other hand, when the required drive power Prdem is in the engine drive range above a predetermined threshold, hybrid control unit 134 establishes the HEV drive mode as the drive mode. Figure 7 The single-point chain line A is the boundary line between the engine drive area and the motor drive area. Figure 7 The predetermined relationship of the boundary lines shown by the dashed line A is an example of a driving area switching map composed of two-dimensional coordinates with the vehicle speed V and the required driving torque Trdem as variables. Figure 7 In FIG. 1 , for convenience, the drive area switching map is shown together with the AT gear shift map.

[0104] When the required drive power Prdem is in the motor drive range, the hybrid control unit 134 also establishes the HEV drive mode when the battery 24's state of charge (SOC) is less than a predetermined engine start threshold, or when warming up the engine 12 is required. In other words, when the battery 24's state of charge (SOC) is less than the engine start threshold, or when warming up the engine 12 is required, the motor drive range in the drive range switching map disappears. The engine start threshold is a predetermined SOC threshold used to determine the need to automatically start the engine 12 to charge the battery 24.

[0105] Furthermore, in the vehicle drive device 10, the engine operating point PNTeng can be changed like a continuously variable transmission by controlling the TM rotating machine MGM. The engine operating point PNTeng is an operating point or an operation point of the engine 12 represented by the engine speed Ne and the engine torque Te.

[0106] Figure 8This is a diagram illustrating that the engine operating point PNTeng can be changed according to the MGM torque Tmgm. Figure 8 In the figure, the equal power lines Lpe indicated by the two-dot chain lines represent examples of the required engine power Pedem required to achieve the required drive power Prdem calculated based on the accelerator opening θacc, etc. The required engine power Pedem is the engine power Pe required by the driver's operation, such as the accelerator operation. Meanwhile, for convenience, the dashed line L01 represents an example of the pump torque Tp, the torque generated by the pump impeller 48a according to the speed ratio e (=Nt / Np) of the torque converter 48, on a two-dimensional coordinate system with the engine speed Ne and the engine torque Te as variables. The pump speed Np is the rotational speed of the pump impeller 48a and has the same value as the engine speed Ne. At a constant turbine speed Nt, the pump torque Tp shows a relationship with the engine speed Ne, which is determined by hardware, as shown by the dashed line L01. Furthermore, when the required engine power Pedem is, for example, the two-dot chain line L02, the engine operating point PNTeng is naturally determined by the point where the dashed line L01 and the two-dot chain line L02 overlap, namely, the so-called coupling point P01.

[0107] For the coupling point P01, for example, by using a portion of the engine power Pe to cause the TM to perform a power generation operation using the rotating machine MGM, the engine operating point PNTeng can be changed to, for example, a fuel efficiency optimum point P02 on the fuel efficiency optimum line Lfl represented by the solid line L03 without changing the required engine power Pedem. The fuel efficiency optimum line Lfl is a predetermined operating curve of the engine 12 showing the relationship between the engine speed Ne and the engine torque Te at which the fuel efficiency of the engine 12 becomes optimum, and is a connection of the fuel efficiency optimum points predetermined as the engine operating point PNTeng that is most suitable for improving the fuel efficiency of the engine 12. In the vehicle drive device 10, the pump torque Tp is balanced by the sum of the engine torque Te and the MGM torque Tmgm, that is, by "Tp=Te+Tmgm( Figure 8By adjusting the MGM torque Tmgm in such a manner that the relationship "(Tmgm is a negative value)" holds true, the engine operating point PNTeng can be arbitrarily changed without being restricted by the turbine speed Nt. When the MGM torque Tmgm is a negative value, that is, when the TM rotating machine MGM is used to generate electricity, the electricity generated by the TM rotating machine MGM is basically supplied to the TF rotating machine MGF and converted into mechanical power by the TF rotating machine MGF. The vehicle drive device 10 includes an electrical conduction path and a mechanical conduction path as a power transmission path for the engine power Pe. The electrical conduction path is an electrical path for electrically transmitting power by sending and receiving electricity between the TM rotating machine MGM and the TF rotating machine MGF, and the mechanical conduction path is a mechanical path for mechanically transmitting power via the torque converter 48. In the vehicle drive device 10, the TM rotating machine MGM and the TF rotating machine MGF are used to form an electric continuously variable transmission.

[0108] The hybrid control unit 134 controls the engine operating point PNTeng by adjusting the amount of power (Ppse [W]), which represents the amount of power transmitted and received in the electrical conduction path between the TM rotating machine MGM and the TF rotating machine MGF. The amount of power transmitted Ppse is, for example, the product of the MGM torque Tmgm and the MGM speed Nmgm.

[0109] The hybrid control unit 134 determines the target electric conduction amount Ppsetgt, which is the electric conduction amount Ppse, for setting the engine operating point PNTeng as the target operating point PNTtgt. The target operating point PNTtgt is, for example, the optimal point for fuel efficiency. When the required engine power Pedem is the double-dashed line L02, it is the optimal point for fuel efficiency P02 (see Figure 8 The target conductance Ppsetgt is the product of the MGM torque Tmgm when the engine operating point PNTeng is changed from the coupling point to the target operating point PNTtgt, and the engine speed Ne at the target operating point PNTtgt, i.e., the MGM speed Nmgm. The hybrid control unit 134 controls the MGM torque Tmgm while driving the TF rotating machine MGF so that the conductance Ppse from the TM rotating machine MGM to the TF rotating machine MGF reaches the target conductance Ppsetgt. This improves the combustion efficiency of the engine 12 even with the same engine power Pe, thereby enhancing the fuel efficiency of the engine 12.

[0110] The driving state control unit 136 determines the mode of the transfer case 28 (see FIG. 1 ) based on the driving state such as the vehicle speed V, the accelerator opening θacc, the longitudinal acceleration Gx and the lateral acceleration Gy, the yaw rate Ryaw, the steering angle θsw and the steering direction Dsw, the lock mode on signal LOCKon, and the wheel slip ratios of the front and rear wheels.Figure 6 ) is established, and various control command signals for establishing the determined mode are output. The various control command signals are, for example, hydraulic control command signals Scbf for the TF clutch CF1, the TF brake BF1, and the switching clutch CD1.

[0111] For example, in the BEV drive mode, the drive state control unit 136 engages the TF brake BF1 and releases the TF clutch CF1 in a relatively low vehicle speed range to establish a low gear position in the differential device 64. On the other hand, in a relatively high vehicle speed range, the drive state control unit 136 releases the TF brake BF1 and engages the TF clutch CF1 to establish a high gear position in the differential device 64. Specifically, in the BEV drive mode, the drive state control unit 136 establishes a "BEV(FF) low" mode in a relatively low vehicle speed range as a drive mode for driving the vehicle 8, and establishes a "BEV(FF) high" mode in a relatively high vehicle speed range.

[0112] For example, when the driving state control unit 136 determines that switching to AWD driving is necessary based on the driving state in the BEV driving mode, the driving state control unit 136 establishes the "BEV_LSD" mode as the driving mode for driving the vehicle 8. For example, when the differential lock selection switch 120 is in the on state in the "BEV_LSD" mode, the driving state control unit 136 establishes the "BEV_Lock" mode as the driving mode for driving the vehicle 8.

[0113] For example, in the HEV drive mode, the drive state control unit 136 establishes the “first power source two-wheel drive (FR)” mode as the drive mode for driving the vehicle 8 .

[0114] For example, when the driving state control unit 136 determines that switching to AWD driving is necessary based on the driving state in the HEV driving mode, the driving state control unit 136 establishes the "first power source torque distribution" mode or the "first power source LSD" mode as the driving mode for driving the vehicle 8. For example, when the differential lock selection switch 120 is turned on in the "first power source torque distribution" mode or the "first power source LSD" mode, the driving state control unit 136 establishes the "first power source lock" mode as the driving mode for driving the vehicle 8.

[0115] The driving state control unit 136, for example, in the "BEV_LSD" mode, the "first power source torque distribution" mode, and the "first power source LSD" mode, determines the driving state of the vehicle 8 based on various signals from various sensors such as the vehicle speed sensor 98, the accelerator opening sensor 102, the acceleration sensor 110, the yaw rate sensor 112, and the steering sensor 114, and sets a target value of the torque distribution ratio Rx corresponding to the determined driving state.

[0116] In the "BEV_LSD" mode, the driving state control unit 136 outputs a hydraulic control command signal Scbf for slip control of the switching clutch CD1. This control adjusts the torque capacity of the switching clutch CD1 so that the torque distribution ratio Rx, for example, the rear-wheel distribution ratio Xr, reaches a target value. As the torque capacity of the switching clutch CD1 increases, the rear-wheel distribution ratio Xr increases, and, in other words, the front-wheel distribution ratio Xf decreases.

[0117] In the "first power source torque distribution" mode, the drive state control unit 136 outputs an MGF control command signal Smgf for controlling the TF rotating machine MGF. This signal adjusts the MGF torque Tmgf generated based on the reaction torque of the TF rotating machine MGF so that, for example, the rear-wheel distribution rate Xr reaches a target value. The greater the MGF torque Tmgf, the smaller the rear-wheel distribution rate Xr.

[0118] In the "first power source LSD" mode, the drive state control unit 136 outputs a hydraulic control command signal Scbf for slip control of the TF clutch CF1. This control adjusts the torque capacity of the TF clutch CF1 so that, for example, the rear-wheel distribution ratio Xr reaches a target value. The greater the torque capacity of the TF clutch CF1, the smaller the rear-wheel distribution ratio Xr.

[0119] Furthermore, when the drive mode switches from the "BEV_LSD" mode (m3 mode), which is the first drive mode, to the "First Power Source Lock" mode (m7 mode), which is the second drive mode, the power source driving the vehicle 8 switches from the second power source PU2 to the first power source PU1. In the "BEV_LSD" mode (m3 mode), the vehicle 8 is placed in an AWD state using the power from the second power source PU2 while slip control is performed on the switching clutch CD1 and the TF clutch CF1 is maintained in the engaged state, thereby controlling the torque distribution ratio Rx. In the "First Power Source Lock" mode (m7 mode), the vehicle 8 is placed in an AWD state using the power from the first power source PU1 while both the switching clutch CD1 and the TF clutch CF1 are maintained in the engaged state and the torque distribution ratio Rx is fixed. When the torque distribution ratio Rx changes with this power source switching, driving stability may be deteriorated.

[0120] Therefore, when switching the driving mode for driving the vehicle 8 from the m3 mode to the m7 mode, the driving state control unit 136 switches the power source for driving the vehicle 8 from the second power source PU2 to the first power source PU1 after switching the switching clutch CD1 from the slipping state to the engaged state while maintaining the TF clutch CF1 in the engaged state. In other words, when switching the driving mode for driving the vehicle 8 from the m3 mode to the m7 mode, the driving state control unit 136 temporarily establishes the m4 mode with a fixed torque distribution ratio Rx. In this state, the power source is switched from the second power source PU2 to the first power source PU1, establishing the m7 mode with a fixed torque distribution ratio Rx.

[0121] When the power source driving the vehicle 8 is switched from the second power source PU2 to the first power source PU1 , if the increase in torque of the first power source PU1 is delayed relative to the decrease in torque of the second power source PU2 , the driving torque Tr may temporarily decrease.

[0122] Therefore, when the power source for driving vehicle 8 is switched from second power source PU2 to first power source PU1, drive state control unit 136 reduces the torque of second power source PU2 in response to the increase in torque of first power source PU1. Specifically, when the power source for driving vehicle 8 is switched from second power source PU2 to first power source PU1, drive state control unit 136 outputs a control command signal for switching from electric motor travel using TF rotating machine MGF to engine travel using first power source PU1 (specifically, engine 12). In this case, drive state control unit 136 outputs, for example, an engine control command signal Se for starting engine 12 and increasing engine torque Te toward a required value for achieving required engine power Pedem, and an MGF control command signal Smgf for decreasing MGF torque Tmgf toward zero in response to the increase in engine torque Te.

[0123] The drive state control unit 136 includes a drive mode determination unit 136a as a drive mode determination unit and a switch completion determination unit 136b as a switch completion determination unit to switch the drive mode between the first drive mode and the second drive mode.

[0124] The driving mode determination unit 136a determines whether the current driving mode is the m3 mode. Furthermore, the driving mode determination unit 136a determines whether a switch from the m3 mode to the m7 mode is determined during driving in the m3 mode.

[0125] When the drive mode determination unit 136a determines that the mode is switched from the m3 mode to the m7 mode, the drive state control unit 136 outputs a hydraulic control command signal Scbf for maintaining the TF clutch CF1 in the engaged state and switching the switching clutch CD1 to the engaged state.

[0126] The switching completion determination unit 136b determines whether the switching of the switching clutch CD1 to the engaged state is completed. In other words, the switching completion determination unit 136b determines whether the switching from the m3 mode to the m4 mode is completed.

[0127] When the switching completion determination unit 136b determines that the switching clutch CD1 has completed switching to the engaged state, the driving state control unit 136 outputs a control command signal for starting the torque of the first power source PU1 and reducing the torque of the second power source PU2 according to the increase in the torque of the first power source PU1.

[0128] The switching completion determination unit 136b determines whether the switching of the power source from the second power source PU2 to the first power source PU1 is completed. In other words, the switching completion determination unit 136b determines whether the switching from the m4 mode to the m7 mode is completed.

[0129] Figure 9 This is a flowchart illustrating a main portion of the control operation of the electronic control device 130 , and is a flowchart illustrating a control operation for suppressing deterioration of driving stability when switching the drive mode accompanying switching of the power source, and is, for example, repeatedly executed.

[0130] exist Figure 9First, in step S10 corresponding to the function of drive mode determination unit 136a (steps omitted hereinafter), a determination is made as to whether the current driving mode is m3 mode. If the determination in S10 is negative, the routine ends. If the determination in S10 is positive, in step S20 corresponding to the function of drive mode determination unit 136a, a determination is made as to whether a switch from m3 mode to m7 mode has been determined. If the determination in S20 is negative, the routine ends. If the determination in S20 is positive, in step S30 corresponding to the function of drive state control unit 136, a hydraulic control command signal Scbf is output for maintaining TF clutch CF1 in the engaged state and switching switching clutch CD1 to the engaged state. In other words, the hydraulic control command signal Scbf is output for switching to the AWD state, i.e., m4 mode, in which the differential device 64 is in the differential lock state and the torque distribution ratio Rx is fixed. Next, in S40 corresponding to the function of the switching completion determination unit 136b, it is determined whether the switching of the switching clutch CD1 to the engaged state is complete. If the determination of S40 is negative, the process returns to the aforementioned S30. If the determination of S40 is positive, in S50 corresponding to the function of the drive state control unit 136, an engine control command signal Se is output for starting the torque of the first power source PU1, for example, the engine torque Te, and increasing the engine torque Te, and an MGF control command signal Smgf is output for reducing the MGF torque Tmgf in accordance with the increase in the engine torque Te. In other words, a control command signal for switching to the m7 mode is output. Next, in S60 corresponding to the function of the switching completion determination unit 136b, it is determined whether the switching of the power source from the second power source PU2 to the first power source PU1 is complete. If the determination of S60 is negative, the process returns to the aforementioned S50. If the determination of S60 is positive, this routine ends.

[0131] As described above, according to this embodiment, when switching the drive mode from m3 mode to m7 mode, the power source is switched from the second power source PU2 to the first power source PU1 after the switching clutch CD1 is switched from a slipping state to an engaged state while the TF clutch CF1 is maintained in the engaged state. This allows the power source to be switched while the torque distribution ratio Rx is fixed. This prevents changes in the torque distribution ratio Rx caused by the power source switch. Consequently, deterioration in driving stability can be suppressed during the drive mode switch associated with the power source switch.

[0132] Furthermore, according to this embodiment, when the power source is switched from the second power source PU2 to the first power source PU1, the torque of the second power source PU2 is reduced according to the increase in the torque of the first power source PU1, thereby suppressing the decrease in the drive torque Tr accompanying the switching of the power source.

[0133] Next, other embodiments of the present invention will be described. Note that in the following description, the same reference numerals are given to the common parts of the embodiments, and the description thereof will be omitted.

[0134] [Example 2]

[0135] As the drive mode switches from the "first power source locked" mode (m7 mode), which is the second drive mode, to the "BEV_LSD" mode (m3 mode), which is the first drive mode, the power source driving vehicle 8 switches from the first power source PU1 to the second power source PU2. This power source switching changes the torque distribution ratio Rx, potentially deteriorating driving stability.

[0136] Therefore, when switching the driving mode for driving the vehicle 8 from the m7 mode to the m3 mode, the driving state control unit 136 switches the switching clutch CD1 from the engaged state to the slipping state while maintaining the TF clutch CF1 in the engaged state after switching the power source for driving the vehicle 8 from the first power source PU1 to the second power source PU2. In other words, when switching the driving mode for driving the vehicle 8 from the m7 mode to the m3 mode, the driving state control unit 136 switches the power source from the first power source PU1 to the second power source PU2 in the m7 mode with a fixed torque distribution ratio Rx, temporarily establishing the m4 mode with a fixed torque distribution ratio Rx, and in this state, performs slip control on the switching clutch CD1 to switch to the m3 mode.

[0137] When the power source driving the vehicle 8 is switched from the first power source PU1 to the second power source PU2 , if the increase in the torque of the second power source PU2 is delayed relative to the decrease in the torque of the first power source PU1 , the driving torque Tr may temporarily decrease.

[0138] Therefore, when the power source for driving vehicle 8 is switched from first power source PU1 to second power source PU2, drive state control unit 136 reduces the torque of first power source PU1 in response to the increase in torque of second power source PU2. Specifically, when the power source for driving vehicle 8 is switched from first power source PU1 to second power source PU2, drive state control unit 136 outputs a control command signal for switching from engine travel using first power source PU1 (particularly engine 12) to electric motor travel using TF rotating machine MGF. In this case, drive state control unit 136 outputs, for example, an MGF control command signal Smgf for increasing MGF torque Tmgf toward a required value for achieving required drive power Prdem, and an engine control command signal Se for reducing engine torque Te toward zero in response to the increase in MGF torque Tmgf, thereby stopping engine 12.

[0139] The driving mode determination unit 136a determines whether the current driving mode is the m7 mode. Furthermore, the driving mode determination unit 136a determines whether a switch from the m7 mode to the m3 mode is determined during driving in the m7 mode.

[0140] When the drive mode determination unit 136a determines that the mode is switched from the m7 mode to the m3 mode, the drive state control unit 136 outputs a control command signal for starting the torque of the second power source PU2 while maintaining the switching clutch CD1 and the TF clutch CF1 in the engaged state and reducing the torque of the first power source PU1 according to the increase in the torque of the second power source PU2.

[0141] The switching completion determination unit 136b determines whether the switching of the power source from the first power source PU1 to the second power source PU2 is completed. In other words, the switching completion determination unit 136b determines whether the switching from the m7 mode to the m4 mode is completed.

[0142] When the switching completion determination unit 136b determines that the power source switching is complete, the driving state control unit 136 outputs a control command signal for switching from the m4 mode to the m3 mode. For example, the driving state control unit 136 outputs a hydraulic control command signal Scbf for slip control of the switching clutch CD1.

[0143] Figure 10 This is a flowchart illustrating a main portion of the control operation of the electronic control device 130 , and is a flowchart illustrating a control operation for suppressing deterioration of driving stability when switching the drive mode accompanying switching of the power source, and is, for example, repeatedly executed. Figure 10 is with Figure 9 Flowcharts of different embodiments.

[0144] exist Figure 10 First, in S10B corresponding to the function of drive mode determination unit 136a, it is determined whether the current driving mode is m7 mode. If the determination in S10B is negative, this routine ends. If the determination in S10B is positive, in S20B corresponding to the function of drive mode determination unit 136a, it is determined whether a switch from m7 mode to m3 mode has been determined. If the determination in S20B is negative, this routine ends. If the determination in S20B is positive, in S30B corresponding to the function of drive state control unit 136, the output of hydraulic control command signal Scbf for engaging both switching clutch CD1 and TF clutch CF1 is maintained. In other words, the AWD differential lock state in which the torque distribution ratio Rx is fixed is maintained. Next, in S40B, corresponding to the function of the drive state control unit 136, an MGF control command signal Smgf is output for initiating and increasing the MGF torque Tmgf. Furthermore, an engine control command signal Se is output for reducing the torque of the first power source PU1, such as the engine torque Te, in response to the increase in the MGF torque Tmgf. In other words, a control command signal for switching to the m4 mode is output. Next, in S50B, corresponding to the function of the switching completion determination unit 136b, a determination is made as to whether the power source switching from the first power source PU1 to the second power source PU2 is complete. If the determination in S50B is negative, the process returns to S40B described above. If the determination in S50B is positive, in S60B, corresponding to the function of the drive state control unit 136, a hydraulic control command signal Scbf is output for slip control of the switching clutch CD1 so that the torque distribution ratio Rx reaches the target value. In other words, a control command signal for switching to the m3 mode is output.

[0145] As described above, according to this embodiment, when the drive mode is switched from m7 mode to m3 mode, after the power source is switched from the first power source PU1 to the second power source PU2, the TF clutch CF1 is maintained in the engaged state while the switching clutch CD1 is switched from the engaged state to the slipping state. This allows the power source to be switched while the torque distribution ratio Rx is fixed. This prevents changes in the torque distribution ratio Rx caused by the power source switching. Consequently, it is possible to suppress deterioration in driving stability during the drive mode switch associated with the power source switch.

[0146] Furthermore, according to this embodiment, when the power source is switched from the first power source PU1 to the second power source PU2, the torque of the first power source PU1 is reduced according to the increase in the torque of the second power source PU2, thereby suppressing the decrease in the drive torque Tr accompanying the switching of the power source.

[0147] [Example 3]

[0148] Figure 11 This is an explanation of the above embodiment Figure 4 FIG. 2 is a diagram showing a schematic structure of a transfer case 200 which is different from the transfer case 28 and is replaced with the transfer case 28 in the vehicle drive device 10. Figure 11 In the transfer case 200, a TF input shaft 204, a differential device 206, a first output shaft 208, a TF clutch CF1, a TF brake BF1, a switching clutch CD1 and a first sprocket 210 are provided in a transfer case 202 which is a non-rotating member (fixed member). In addition, the transfer case 200 includes a second output shaft 212 and a second sprocket 214 which are provided in the transfer case 202 and are provided on a common rotation axis CL2. In addition, the transfer case 200 includes a TF rotating machine MGF and a chain 216 in the transfer case 202. The TF rotating machine MGF, the differential device 206, the TF clutch CF1, the TF brake BF1, the switching clutch CD1 and the first sprocket 210 are configured to be roughly symmetrical with respect to the rotation axis CL1. Figure 11 The second sprocket 214 is configured to be substantially symmetrical with respect to the rotation axis CL2. Figure 11 In the transfer case 200, the rotation axis CL1 is the axis of the transmission output shaft 54, the first output shaft 208, etc. In the transfer case 200, the rotation axis CL2 is the axis of the second output shaft 212, the front propeller shaft 30, etc.

[0149] The chain 216 is wound between the first sprocket 210 and the second sprocket 214 to connect them. In other words, the first sprocket 210 and the second sprocket 214 are connected via the chain 216 in a power-transmittable manner.

[0150] The TF input shaft 204 is connected to the transmission output shaft 54 ​​in a manner that can transmit power. The first output shaft 208 is connected to the rear drive shaft 32 in a manner that can transmit power. The TF input shaft 204 and the first output shaft 208 are connected integrally. Thus, the power from the first power source PU1 is input to the first output shaft 208 via the automatic transmission 50, etc. In addition, the power input to the first output shaft 208 is transmitted to the rear wheel 16 via the rear drive shaft 32, etc. The first output shaft 208 is a first output rotating member that is input with power from the first power source PU1 and outputs power to the rear wheel 16, which is one of the front wheels 14 and the rear wheels 16. It should be noted that the TF input shaft 204 and the first output shaft 208 can also be a single rotating shaft.

[0151] The second output shaft 212 is connected to the front propeller shaft 30 in a power-transmittable manner. Thus, power input to the second output shaft 212 is transmitted to the front wheel 14 via the front propeller shaft 30 and other means. The second output shaft 212 is a second output rotating member that outputs power to the front wheel 14, which is the other of the front wheel 14 and the rear wheel 16. The second sprocket 214 is fixed to the second output shaft 212 in a relatively non-rotatable manner.

[0152] Differential device 206 is a single-pinion planetary gear device comprising a sun gear S, a carrier CA, and a ring gear R. The TF rotating machine MGF is connected to sun gear S in a power-transmittable manner. Carrier CA is connected to the TF input shaft 204 and the first output shaft 208. Ring gear R is selectively connected to transfer case 202 via TF brake BF1. Furthermore, ring gear R is selectively connected to first sprocket 210 via switching clutch CD1. Sun gear S and carrier CA are selectively connected via TF clutch CF1.

[0153] Figure 12 is a collinear diagram showing the relative relationship between the rotational speeds of the various rotating elements in the transfer case 200. Figure 12 In the figure, the three vertical lines Y1, Y2, and Y3 corresponding to the three rotating elements constituting the differential device 206 of the transfer case 200 are axes that, from the left, represent 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 vertical line Y0 shown to the left of the vertical line Y1 is an axis that represents the rotational speeds of the TF input shaft 204 and the first output shaft 208 corresponding to the input and output rotating element RE10.

[0154] If you use Figure 12 , in the transfer case 200, the input / output rotating element RE10 is connected to the carrier CA and to the rear propeller shaft 32. The input / output rotating element RE10 is connected to the first power source PU1 via the hybrid transmission 26 in a power-transmittable manner.

[0155] In the differential device 206, the first rotating element RE1 is connected to the TF rotating machine MGF in a power-transmitting manner. The second rotating element RE2 is connected to the first output shaft 208, which is an output rotating element of one of the first output shaft 208 and the second output shaft 212. The third rotating element RE3 is selectively connected to the second output shaft 212 via the switching clutch CD1, and is selectively connected to the transfer case 202 via the TF brake BF1. The switching clutch CD1 is a first engagement device that selectively connects the third rotating element RE3 to the second output shaft 212, which is an output rotating element of the other of the first output shaft 208 and the second output shaft 212. The first rotating element RE1 and the second rotating element RE2 are selectively connected via the TF clutch CF1. The TF clutch CF1 is a second engagement device that selectively connects any two rotating elements among the first rotating element RE1, the second rotating element RE2, and the third rotating element RE3. In the differential device 206 , the relationship among the rotational speeds of the first rotational element RE1 , the second rotational element RE2 , and the third rotational element RE3 is represented by a straight line Lcd.

[0156] The differential device 206 functions as a transmission device that selectively establishes a high gear speed when the TF clutch CF1 is engaged and a low gear speed when the TF brake BF1 is engaged.

[0157] The differential device 206 functions as a center differential. Specifically, when both the TF clutch CF1 and the TF brake BF1 are released, the differential device 206 can perform a differential operation. In this state, the differential device 206 can use the reaction torque of the TF rotating machine MGF coupled to the first rotating element RE1 to distribute the torque from the first power source PU1, which is input to the second rotating element RE2, to the third rotating element RE3. Alternatively, instead of using the reaction torque of the TF rotating machine MGF, the differential device 206 can limit its differential operation by placing the TF clutch CF1 in a slipping or engaged state. This allows the torque from the first power source PU1, which is input to the second rotating element RE2, to be distributed to the third rotating element RE3. In this case, in the transfer case 200, when the switching clutch CD1 is engaged or slipping, the torque distributed to the third rotating element RE3 is transmitted to the second output shaft 212. Thus, the transfer case 200 is a torque distribution device that distributes part of the torque from the first power source PU1 input to the first output shaft 208 to the second output shaft 212. Thus, the transfer case 200 can distribute the torque to the front wheels 14 and the rear wheels 16.

[0158] Figure 13is a working engagement table that shows the relationship between the modes established in the transfer 200 and the control states of the engagement devices in the transfer 200. In Figure 13 In the working engagement table in Figure 13 Figure 6 The difference from the working engagement table in

[0159] The "BEV (FR) high" mode of the number m1 and the "BEV (FR) low" mode of the number m2 are BEV drive modes in which the vehicle 8 is driven by the TF rotary machine MGF. In the "BEV (FR) high" mode and the "BEV (FR) low" mode, the switching clutch CD1 is released, and thus the power transmission between the differential device 206 and the front wheels 14 is cut off. In this state, in the differential device 206 in which the high gear stage based on the engagement state of the TF clutch CF1 or the low gear stage based on the engagement state of the TF brake BF1 is formed, the power from the TF rotary machine MGF is transmitted to the rear wheels 16 side via the first output shaft 208. Thus, the BEV travel of the present embodiment is realized by rear wheel drive travel.

[0160] The "first drive source torque distribution" mode of the number m5 is a mode in which, for example, the differential device 206 in the same state as the high gear stage receives the torque from the first power source PUI transmitted to the differential device 206 from the first output shaft 208 by the reaction torque of the TF rotary machine MGF with the sun gear S, and thus distributes the torque of the first power source PUI to the front wheels 14 and the rear wheels 16 at an arbitrary ratio desired to correspond to the reaction torque of the TF rotary machine MGF. In the "first drive source torque distribution" mode in the transfer 200, the TF rotary machine MGF is caused to regenerate. The electric power generated by the regeneration of the TF rotary machine MGF is, for example, charged to the battery 24. In this way, the transfer 200 of the present embodiment causes the TF rotary machine MGF to regenerate in the "first drive source torque distribution" mode, and thus cannot implement the travel mode in which the electric conduction path is used and the electric power generated by the TM rotary machine MGM is supplied as the power for the motoring operation of the TF rotary machine MGF in the "first drive source torque distribution" mode.

[0161] ​Even with the transfer case 200 constructed as described above, similarly to the aforementioned embodiments 1 and 2, when the drive mode is switched between the m3 mode and the m7 mode, the power source is switched by switching the drive mode between the m4 mode and the m7 mode in which the torque distribution ratio Rx is fixed, thereby suppressing the deterioration of driving stability when the drive mode is switched accompanying the switching of the power source.

[0162] [Example 4]

[0163] Figure 14 This is an explanation of the above embodiment Figure 4 The transfer case 300 of this embodiment is different from the transfer case 300 of the present invention, and is replaced with the transfer case 28 in the vehicle drive device 10. Figure 4 The transfer case 28 shown here differs in that a first output shaft 302, serving as a first output rotating member that receives power from the first power source PU1 and outputs power to one of the front and rear wheels 14, 16, is connected to the front wheel 14 via the front propeller shaft 30 or the like in a power-transferable manner. Furthermore, a second output shaft 304, serving as a second output rotating member that outputs power to the other of the front and rear wheels 14, 16, is connected to the rear wheel 16 via the rear propeller shaft 32 or the like in a power-transferable manner. Therefore, in this embodiment, one of the front and rear wheels 14, 16 is the front wheel 14, and the other is the rear wheel 16. The specific connection relationship of the differential device 306 is essentially the same as that of the differential device 64. In other words, the transfer case 300 is equivalent to the transfer case 28 with the front and rear wheels 14, 16 swapped. Other than this, the transfer case 300 is essentially the same as the transfer case 28. As described above, the structure of the transfer case 300 is basically the same as that of the aforementioned transfer case 28 , and therefore detailed description thereof will be omitted.

[0164] Figure 15 is a collinear diagram showing the relative relationship between the rotational speeds of the respective rotating elements in the transfer case 300. Figure 15 The nomogram of the embodiment described above is Figure 5 The nomogram shown in FIG. 1 only swaps the positions of the front wheels 14 and the rear wheels 16. Figure 5 The collinear diagram of is substantially unchanged, so detailed description is omitted. It should be noted that one of the first output shaft 302 and the second output shaft 304 is the second output shaft 304 , and the other is the first output shaft 302 .

[0165] Figure 16 This is an operation engagement table that explains the relationship between each mode established in the transfer 300 and the control state of each engagement device in the transfer 300. Figure 16The work card table is only in the aforementioned embodiment Figure 6 In the operation engagement table, the "BEV (FF) High" mode of number m1 and the "BEV (FF) Low" mode of number m2 are changed to the "BEV (FR) High" mode and the "BEV (FR) Low" mode, respectively, and the "First Power Source Two-Wheel Drive (FR)" mode of number m8 is changed to the "First Power Source Two-Wheel Drive (FF)". That is, in the transfer case 300, only the driving state of the front wheels 14 and rear wheels 16 in each mode is exchanged with the driving state of the front wheels 14 and rear wheels 16 in the transfer case 28, so the connection with the front wheels 14 and rear wheels 16 is omitted. Figure 16 Related detailed instructions.

[0166] Even with the transfer case 300 constructed as described above, similarly to the aforementioned first and second embodiments, when the drive mode is switched between the m3 mode and the m7 mode, the power source is switched by switching the drive mode between the m4 mode and the m7 mode in which the torque distribution ratio Rx is fixed, thereby suppressing the deterioration of driving stability when the drive mode is switched accompanying the switching of the power source.

[0167] [Example 5]

[0168] Figure 17 This is an explanation of the above embodiment Figure 4 The transfer case 400 of this embodiment is different from the transfer case 28 of the embodiment of the present invention. Figure 11 The transfer case 200 shown in the figure is different in that: the first output shaft 402, which is a first output rotating member that receives power from the first power source PU1 and outputs power to one of the front wheels 14 and the rear wheels 16, is connected to the front wheel 14 via the front drive shaft 30 or the like in a manner capable of transmitting power; and the second output shaft 404, which is a second output rotating member that outputs power to the other of the front wheels 14 and the rear wheels 16, is connected to the rear wheel 16 via the rear drive shaft 32 or the like in a manner capable of transmitting power. Therefore, in this embodiment, one of the front wheels 14 and the rear wheels 16 is the front wheel 14, and the other wheel is the rear wheel 16. In addition, the specific connection relationship of the differential device 406 is the same as that of the embodiment. Figure 11 The differential device 206 is essentially unchanged. Specifically, the transfer case 400 is equivalent to the transfer case 200 with the front wheels 14 and rear wheels 16 swapped. Otherwise, the transfer case 400 is essentially unchanged from the transfer case 200. Thus, the structure of the transfer case 400 is essentially unchanged from the aforementioned transfer case 200, and therefore a detailed description thereof will be omitted.

[0169] Figure 18 It is a collinear diagram showing the relative relationship between the rotational speeds of the respective rotating elements in the transfer case 400.Figure 18 The nomogram of the embodiment described above is Figure 12 The nomogram shown in FIG. 1 only swaps the positions of the front wheels 14 and the rear wheels 16. Figure 12 The collinear diagram of is substantially unchanged, so detailed description is omitted. It should be noted that one of the first output shaft 402 and the second output shaft 404 is the first output shaft 402 , and the other is the second output shaft 404 .

[0170] Figure 19 This is an operation engagement table that explains the relationship between each mode established in the transfer 400 and the control state of each engagement device in the transfer 400. Figure 19 The work card table is only in the aforementioned embodiment Figure 13 In the operation engagement table, the "BEV (FR) High" mode of number m1 and the "BEV (FR) Low" mode of number m2 are changed to the "BEV (FF) High" mode and the "BEV (FF) Low" mode, respectively, and the "First Power Source Two-Wheel Drive (FR)" mode of number m8 is changed to the "First Power Source Two-Wheel Drive (FF)". That is, in the transfer case 400, only the driving state of the front wheels 14 and rear wheels 16 in each mode is exchanged with the driving state of the front wheels 14 and rear wheels 16 in the transfer case 200, so the connection with the front wheels 14 and rear wheels 16 is omitted. Figure 19 Related detailed instructions.

[0171] Even with the transfer case 400 constructed as described above, similarly to the aforementioned first and second embodiments, when the driving mode is switched between the m3 mode and the m7 mode, the power source is switched by switching the driving mode between the m4 mode and the m7 mode in which the torque distribution ratio Rx is fixed, thereby suppressing the deterioration of driving stability when the driving mode is switched accompanying the switching of the power source.

[0172] As mentioned above, although the embodiment of the present invention was described in detail based on the drawings, the present invention is also applicable to other aspects.

[0173] For example, the aforementioned embodiment 1 and embodiment 2 may be implemented separately or in combination.

[0174] In the aforementioned embodiments, the transfer cases 28, 200, 300, and 400 only need to include the switching clutch CD1 and the TF clutch CF1, respectively, of the switching clutch CD1, the TF clutch CF1, and the TF brake BF1. Furthermore, the TF clutch CF1 can be any clutch that selectively connects any two of the first, second, and third rotational elements RE1, RE2, and RE3. It can be a clutch that selectively connects the first and third rotational elements RE1 and RE3 of the differential devices 64, 206, 306, and 406, for example.

[0175] In the aforementioned embodiments, the sun gear S of the differential devices 64, 206, 306, and 406 functions as the first rotating element RE1, the carrier CA functions as the second rotating element RE2, and the ring gear R functions as the third rotating element RE3. However, the present invention is not necessarily limited to this. For example, the first rotating element RE1 may be either the carrier CA or the ring gear R, and the second rotating element RE2 and the third rotating element RE3 may also be appropriately modified. In other words, the connection relationship of the differential devices 64, 206, 306, and 406 may be appropriately modified within a range that does not conflict with the requirements. Furthermore, while the sun gear S of the differential devices 64, 206, 306, and 406 is directly connected to the TF rotating machine MGF, a speed reducer or speed increaser may be interposed between the TF rotating machine MGF and the sun gear S of the differential device 64. Furthermore, the differential devices 64, 206, 306, and 406 do not necessarily need to be planetary gear devices; for example, they may be configured as differential mechanisms having three rotating elements and capable of differential operation.

[0176] Furthermore, in the aforementioned embodiment, the first power source PU1 may include at least one of the engine 12 and the TM rotating machine MGM. For example, if the first power source PU1 is solely the TM rotating machine MGM, or if a clutch capable of disconnecting the engine 12 from the power transmission path is provided, the torque converter 48 and the automatic transmission 50 may not necessarily be provided. Furthermore, the automatic transmission 50 may be a synchromesh-type parallel 2-axis automatic transmission, including the well-known DCT (Dual Clutch Transmission), or a well-known belt-type continuously variable transmission. Furthermore, the torque converter 48 may be replaced with another fluid-type transmission device, such as a fluid coupling, that does not have a torque amplification function, or may be replaced with a simple clutch. Furthermore, the second power source PU2 may include an engine in addition to the TF rotating machine MGF, or may use an engine in place of the TF rotating machine MGF.

[0177] Furthermore, in the aforementioned embodiment, the vehicle drive device 10 is arranged longitudinally, with the rotation axis CL1 of the engine 12 crankshaft, the automatic transmission 50, the transfer cases 28, 200, 300, 400, and the like being parallel to the direction of travel of the vehicle 8. However, the present invention is not necessarily limited to this configuration. For example, the vehicle drive device may also be arranged transversely, with the crankshaft of the engine 12, the rotation axis of the automatic transmission 50, and the rotation axes of the transfer cases 28, 200, 300, 400 being arranged in the vehicle width direction.

[0178] It should be noted that the above-mentioned content is merely one embodiment, and the present invention can be implemented in various forms with various changes and improvements added based on the knowledge of those skilled in the art.

Claims

1. A vehicle drive device, the vehicle drive device comprising: a first power source; a first output rotating member, the first output rotating member receiving power from the first power source and outputting power to one of the front and rear wheels; a second output rotating member, the second output rotating member outputting power to the other of the front and rear wheels; a second power source; and a differential device having a first rotating element connected to the second power source, a second rotating element connected to one of the first and second output rotating members, and a third rotating element. a first engagement device that selectively connects the third rotating element to the other of the first output rotating member and the second output rotating member; a second engaging device, configured to selectively connect any two of the first rotating element, the second rotating element, and the third rotating element; and a control device, characterized in that The control device can establish a first driving mode and a second driving mode as driving modes for driving the vehicle. In the first driving mode, the first engaging device is controlled to be in a slipping state and the second engaging device is maintained in an engaged state, while the vehicle is put into an all-wheel drive state by the power from the second power source, and the torque distribution ratio between the front wheels and the rear wheels is controlled. In the second driving mode, the first engaging device and the second engaging device are both maintained in the engaged state and the torque distribution ratio is fixed, while the vehicle is put into an all-wheel drive state by the power from the first power source. When the driving mode is switched from the first driving mode to the second driving mode, the first engaging device is switched from a slipping state to an engaging state while the second engaging device is maintained in an engaged state, and then the power source for driving the vehicle is switched from the second power source to the first power source.

2. The vehicle drive device according to claim 1, wherein: The control device reduces the torque of the second power source in response to an increase in the torque of the first power source when switching the power source from the second power source to the first power source.

3. A vehicle drive device, comprising: a first power source; a first output rotating member, the first output rotating member receiving power from the first power source and outputting power to one of the front and rear wheels; a second output rotating member, the second output rotating member outputting power to the other of the front and rear wheels; a second power source; and a differential device having a first rotating element connected to the second power source, a second rotating element connected to one of the first and second output rotating members, and a third rotating element. a first engagement device that selectively connects the third rotating element to the other of the first output rotating member and the second output rotating member; a second engaging device, configured to selectively connect any two of the first rotating element, the second rotating element, and the third rotating element; and a control device, characterized in that The control device can establish a first driving mode and a second driving mode as driving modes for driving the vehicle. In the first driving mode, the first engaging device is controlled to be in a slipping state and the second engaging device is maintained in an engaged state, while the vehicle is put into an all-wheel drive state by the power from the second power source, and the torque distribution ratio between the front wheels and the rear wheels is controlled. In the second driving mode, the first engaging device and the second engaging device are both maintained in the engaged state and the torque distribution ratio is fixed, while the vehicle is put into an all-wheel drive state by the power from the first power source. When the driving mode is switched from the second driving mode to the first driving mode, after the power source driving the vehicle is switched from the first power source to the second power source, the first engaging device is switched from the engaged state to the slipping state while the second engaging device is maintained in the engaged state.

4. The vehicle drive device according to claim 3, wherein: The control device reduces the torque of the first power source in response to an increase in the torque of the second power source when the power source is switched from the first power source to the second power source.

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