Hybrid vehicles

Abstract

To provide a hybrid vehicle that can smoothly perform gear change without using a plurality of clutches, downsize a transmission and reduce manufacturing costs of the transmission.SOLUTION: A transmission 3 is provided with: an input shaft 41 to which driving force of an engine 2 is transmitted; an intermediate shaft 42 of an odd number stage; an intermediate shaft 43 of an even number stage; an output shaft 44; a motor generator 23 of the odd number stage; a motor generator 24 of the even number stage; a first speed gear pair 45 and a third speed gear pair 47 which connect the intermediate shaft 42 of the odd number stage to the output shaft 44 so that driving force can be transmitted; a second speed gear pair 46 and a fourth speed gear pair 48 which connect the intermediate shaft 43 of the odd number stage to the output shaft 44 so that driving force can be transmitted; and a first dog clutch 52 that can be switched between an odd number stage position where the input shaft 41 is connected to the intermediate shaft 42 of the odd number stage and an even number stage position where the input shaft 41 is connected to the intermediate shaft 43 of the even number stage.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to hybrid vehicles. [Background technology]

[0002] BACKGROUND ART Hybrid vehicles equipped with a dual-clutch transmission having two clutches have been known in the past (see Patent Document 1).

[0003] This dual-clutch transmission comprises an input system including a first input shaft connected to the internal combustion engine via a first clutch and a second input shaft connected to the internal combustion engine via a second clutch; an output system connected to the drive wheels so as to transmit driving force; and a plurality of gear trains, some of which are interposed between the first input shaft and the output system and the rest of which are interposed between the second input shaft and the output system, and which have different gear ratios from each other.

[0004] The dual-clutch transmission also includes a first motor generator connected to the first input shaft so as to be able to transmit driving force, and a second motor generator connected to the second input shaft so as to be able to transmit driving force, and operates in an engine driving mode in which either the first clutch or the second clutch is switched to an engaged state to drive the drive wheels with the internal combustion engine, and a motor driving mode in which the internal combustion engine is stopped and the drive wheels are driven by either the first motor generator or the second motor generator. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-201126 Summary of the Invention [Problem to be solved by the invention]

[0006] However, conventional dual-clutch transmissions require two sets of clutches, a first clutch and a second clutch, which increases the size of the transmission and the manufacturing costs of the transmission.

[0007] The present invention has been made in light of the above-mentioned circumstances, and aims to provide a hybrid vehicle that can smoothly change gears without using multiple clutches, can reduce the size of the transmission, and can reduce the manufacturing costs of the transmission. [Means for solving the problem]

[0008] The present invention relates to a hybrid vehicle having a transmission that changes the speed of a driving force of an internal combustion engine and transmits the driving force to drive wheels, the transmission comprising: an input shaft to which the driving force of the internal combustion engine is transmitted; a first intermediate shaft that is provided coaxially with the input shaft and rotatable relative to the input shaft; a second intermediate shaft that is provided coaxially with the input shaft and opposed to the first intermediate shaft in the axial direction of the input shaft and rotatable relative to the input shaft; an output shaft that is provided in parallel to the first intermediate shaft and the second intermediate shaft and transmits the driving force to the drive wheels; and a second intermediate shaft that is connected to the first intermediate shaft so as to be able to transmit the driving force. a first rotating electric machine, a second rotating electric machine connected to the second intermediate shaft so as to be able to transmit driving force; a first gear pair connecting the first intermediate shaft and the output shaft so as to be able to transmit driving force and constituting a plurality of gear stages with different gear ratios; a second gear pair connecting the second intermediate shaft and the output shaft so as to be able to transmit driving force and constituting a plurality of gear stages with gear ratios different from the gear ratio of the first gear pair; and a first switching member switchable among a neutral position, a first position at which the input shaft and the first intermediate shaft are connected, and a second position at which the input shaft and the second intermediate shaft are connected. the first gear pair has a plurality of first intermediate shaft side gears provided to be rotatable integrally with the first intermediate shaft, and a plurality of first output shaft side gears provided to be rotatable relatively to the output shaft and meshing with the plurality of first intermediate shaft side gears, respectively; the second gear pair has a plurality of second intermediate shaft side gears provided to be rotatable integrally with the second intermediate shaft, and a plurality of second output shaft side gears provided to be rotatable relatively to the output shaft and meshing with the plurality of second intermediate shaft side gears, respectively; and the transmission connects any one of the plurality of first output shaft side gears to the output shaft. a second switching member that connects one of the plurality of second output shaft side gears to the output shaft and rotates integrally with the output shaft, thereby establishing a gear stage corresponding to the first gear pair; a third switching member that connects any one of the plurality of second output shaft side gears to the output shaft and rotates integrally with the output shaft, thereby establishing a gear stage corresponding to the second gear pair; a first rotating electric machine gear pair that connects the first rotating electric machine and the first intermediate shaft so as to be able to transmit a driving force; and a second rotating electric machine gear pair that connects the second rotating electric machine and the second intermediate shaft so as to be able to transmit a driving force, and the first rotating electric machine gear pair has a first drive gear attached to the first rotating electric machine and a first driven gear provided so as to be rotatable integrally with the first intermediate shaft and meshing with the first drive gear, and the second rotating electric machine gear pair has a second drive gear attached to the second rotating electric machine and a second driven gear provided so as to be rotatable integrally with the second intermediate shaft and meshing with the second drive gear, and the first driven gear is provided closest to the first switching member in the axial direction of the first intermediate shaft. and the first intermediate shaft side gear is installed on the opposite side of the first switching member with respect to the first driven gear, the second driven gear is installed closest to the first switching member in the axial direction of the second intermediate shaft, and the second intermediate shaft side gear is installed on the opposite side of the second driven gear from the first switching member, and the first intermediate shaft side gear and the first driven gear are installed so that their diameters gradually decrease as they become farther away from the first switching member in the axial direction of the first intermediate shaft, and the second intermediate shaft side gear and the second driven gear areThe second intermediate shaft is disposed so that its diameter gradually decreases as it moves away from the first switching member in the axial direction. It is characterized by: [Effects of the Invention]

[0009] As described above, according to the present invention, gear changes can be smoothly performed without using multiple clutches, the size of the transmission can be reduced, and the manufacturing costs of the transmission can be reduced. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing the configuration of a hybrid vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing the configuration of a transmission for a hybrid vehicle according to one embodiment of the present invention. [Figure 3] FIG. 3 is a diagram showing driving modes of a hybrid vehicle according to an embodiment of the present invention. [Figure 4] FIG. 4 is a timing chart of the shift control executed by the hybrid vehicle according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] A hybrid vehicle according to one embodiment of the present invention is a hybrid vehicle having a transmission that changes the speed of a driving force of an internal combustion engine and transmits it to drive wheels, and the transmission includes an input shaft to which the driving force of the internal combustion engine is transmitted, a first intermediate shaft that is arranged coaxially with the input shaft and rotatable relative to the input shaft, a second intermediate shaft that is arranged coaxially with the input shaft and opposed to the first intermediate shaft in the axial direction of the input shaft and rotatable relative to the input shaft, an output shaft that is arranged parallel to the first intermediate shaft and the second intermediate shaft and transmits the driving force to the drive wheels, and a second intermediate shaft that is connected to the first intermediate shaft so as to be able to transmit the driving force. the first rotating electric machine connected to a second intermediate shaft so as to be able to transmit driving force; a first gear pair connecting the first intermediate shaft to an output shaft so as to be able to transmit driving force and constituting a plurality of gear stages with different gear ratios; a second gear pair connecting the second intermediate shaft to the output shaft so as to be able to transmit driving force and constituting a plurality of gear stages with gear ratios different from that of the first gear pair; and a first switching member switchable between a neutral position, a first position at which the input shaft and the first intermediate shaft are connected, and a second position at which the input shaft and the second intermediate shaft are connected.

[0012] As a result, the hybrid vehicle according to one embodiment of the present invention can smoothly change gears without using multiple clutches, allowing the transmission to be made smaller and the manufacturing costs of the transmission to be reduced. [Example]

[0013] A hybrid vehicle according to an embodiment of the present invention will now be described with reference to the drawings, in which: Figures 1 to 4 show a hybrid vehicle according to an embodiment of the present invention.

[0014] First, the configuration will be described. As shown in FIG. 1, a hybrid vehicle 1 (hereinafter referred to as vehicle 1) includes an engine 2 as an internal combustion engine, a transmission 3, drive wheels 4L, 4R, an HCU (Hybrid Control Unit) 10 that comprehensively controls the vehicle 1, an ECU (Engine Control Unit) 11 that controls the engine 2, a TCU (Transmission Control Unit) 12 that controls the transmission 3, a BMS (Battery Management System) 13, an odd-stage inverter 14, an even-stage inverter 15, and a battery 16.

[0015] The engine 2 is formed with a plurality of cylinders. In this embodiment, the engine 2 is configured to perform a series of four strokes for each cylinder, including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke.

[0016] The transmission 3 changes the driving force (rotation speed) output from the engine 2 and transmits it to the left and right driving wheels 4L, 4R via left and right drive shafts 31L, 31R, thereby driving the driving wheels 4L, 4R.

[0017] The transmission 3 includes a speed change mechanism 21, a differential device 22, an odd-numbered stage motor generator 23, an even-numbered stage motor generator 24, and an actuator 25.

[0018] The transmission 3 is configured as a so-called AMT (Automated Manual Transmission), and the gear stages are changed by an actuator 25 controlled by the TCU 12.

[0019] The differential device 22 transmits the driving force output by the transmission mechanism 21 to the driving wheels 4L, 4R via the drive shafts 31L, 31R.

[0020] 2, the transmission mechanism 21 includes an input shaft 41, a cylindrical odd-numbered intermediate shaft 42, a cylindrical even-numbered intermediate shaft 43, and an output shaft 44. The input shaft 41, the odd-numbered intermediate shaft 42, the even-numbered intermediate shaft 43, and the output shaft 44 extend in the width direction of the vehicle 1 (hereinafter referred to as the vehicle width direction). The traveling direction of the vehicle 1 is the front-rear direction, and the vehicle width direction is the left-right direction.

[0021] In this embodiment, the odd-numbered stage intermediate shaft 42 constitutes a first intermediate shaft, and the even-numbered stage intermediate shaft 43 constitutes a second intermediate shaft.

[0022] The input shaft 41 is connected to the crankshaft 2S of the engine 2 via a joint 33 made of a damper, and the driving force (engine torque) of the engine 2 is transmitted to the input shaft 41 via the joint 33. The joint 33 constantly connects the crankshaft 2S and the input shaft 41 so that the driving force can be transmitted between the crankshaft 2S and the input shaft 41.

[0023] The coupling 33 absorbs torque fluctuations and rotational fluctuations transmitted from the crankshaft 2S of the engine 2 to the input shaft 41 when the vehicle 1 accelerates, and absorbs torque fluctuations and rotational fluctuations transmitted from the input shaft 41 to the engine 2 when the vehicle 1 decelerates.

[0024] The odd-numbered-stage intermediate shaft 42 is located outside the input shaft 41, is coaxial with the input shaft 41, and is rotatable relative to the input shaft 41. In other words, the input shaft 41 is inserted into the cylindrical odd-numbered-stage intermediate shaft 42, and the odd-numbered-stage intermediate shaft 42 is supported by the input shaft 41 so as to be rotatable relative to the input shaft 41.

[0025] The even-numbered intermediate shaft 43 is located outside the input shaft 41, is coaxial with the input shaft 41, and is rotatable relative to the input shaft 41. In other words, the input shaft 41 is inserted into the cylindrical even-numbered intermediate shaft 43, and the even-numbered intermediate shaft 43 is supported by the input shaft 41 so as to be rotatable relative to the input shaft 41.

[0026] The even-numbered stage intermediate shaft 43 faces the odd-numbered stage intermediate shaft 42 in the axial direction of the input shaft 41, and is installed on the opposite side of the odd-numbered stage intermediate shaft 42 from the engine 2. In other words, the engine 2, the odd-numbered stage intermediate shaft 42, and the even-numbered stage intermediate shaft 43 are arranged in this order from the left side in the axial direction of the input shaft 41.

[0027] The input shaft 41, the odd-numbered intermediate shafts 42, and the even-numbered intermediate shafts 43 are installed coaxially in parallel, and the input shaft 41, the odd-numbered intermediate shafts 42, and the even-numbered intermediate shafts 43 have the same rotation center axis.

[0028] The output shaft 44 is installed in parallel with the odd-numbered stage intermediate shaft 42 and the even-numbered stage intermediate shaft 43, and extends leftward beyond the left end of the odd-numbered stage intermediate shaft 42 and rightward beyond the right end of the even-numbered stage intermediate shaft 43.

[0029] The odd-numbered intermediate shaft 42 and the output shaft 44 are configured to be able to transmit driving force via a first-speed gear pair 45 and a third-speed gear pair 47. In other words, the first-speed gear pair 45 and the third-speed gear pair 47 are configured to be able to connect the odd-numbered intermediate shaft 42 and the output shaft 44 so as to transmit driving force from the odd-numbered intermediate shaft 42 to the output shaft 44 and also to transmit driving force from the output shaft 44 to the odd-numbered intermediate shaft 42, and form a first gear pair having odd-numbered gears with different gear ratios.

[0030] The first-speed gear pair 45 has a first-speed input gear 45A and a third-speed input gear 47A that are rotatable integrally with the odd-numbered intermediate shaft 42, and has a first-speed output gear 45B and a third-speed output gear 47B that are rotatable relative to the output shaft 44 and mesh with the first-speed input gear 45A and the third-speed input gear 47A, respectively.

[0031] An odd-numbered motor driven gear 50B is provided on the odd-numbered intermediate shaft 42. The odd-numbered motor driven gear 50B is formed to have a larger diameter than the third-speed input gear 47A, which is formed to have a larger diameter than the first-speed input gear 45A.

[0032] An odd-numbered stage motor drive gear 50A is attached to the output shaft 23A of the odd-numbered stage motor generator 23, and the odd-numbered stage motor drive gear 50A meshes with an odd-numbered stage motor driven gear 50B.

[0033] In this embodiment, the odd-numbered motor drive gear 50A and the odd-numbered motor driven gear 50B constitute a first rotating electrical gear pair. The odd-numbered motor drive gear 50A constitutes the first drive gear, and the odd-numbered motor driven gear 50B constitutes the first driven gear.

[0034] The driving force of odd-numbered motor generator 23 is transmitted from odd-numbered motor drive gear 50A via odd-numbered motor driven gear 50B to odd-numbered intermediate shaft 42. Odd-numbered motor generator 23 is disposed on the left side of odd-numbered motor drive gear 50A in the axial direction of input shaft 41. In other words, odd-numbered motor generator 23 is disposed in the same position as first-speed input gear 45A or third-speed input gear 47A in the axial direction of input shaft 41.

[0035] The odd-numbered stage motor drive gear 50A is formed with a smaller diameter than the odd-numbered stage motor driven gear 50B, and the rotational speed of the driving force transmitted from the odd-numbered stage motor generator 23 to the odd-numbered stage intermediate shaft 42 is reduced by the odd-numbered stage motor drive gear 50A and the odd-numbered stage motor driven gear 50B.

[0036] The first-speed output gear 45B is formed to have a larger diameter than the first-speed input gear 45A, and the third-speed output gear 47B is formed to have a smaller diameter than the third-speed input gear 47A.

[0037] The even-numbered intermediate shaft 43 and the output shaft 44 are configured to be able to transmit driving force via a second-speed gear pair 46 and a fourth-speed gear pair 48. In other words, the second-speed gear pair 46 and the fourth-speed gear pair 48 are configured to be able to connect the even-numbered intermediate shaft 43 and the output shaft 44 so as to transmit driving force from the even-numbered intermediate shaft 43 to the output shaft 44 and also to transmit driving force from the output shaft 44 to the even-numbered intermediate shaft 43, and form a second gear pair having even-numbered gears with different gear ratios.

[0038] The second-speed gear pair 46 has a second-speed input gear 46A and a fourth-speed input gear 48A that are rotatable integrally with the even-stage intermediate shaft 43, and has a second-speed output gear 46B and a fourth-speed output gear 48B that are rotatable relative to the output shaft 44 and mesh with the second-speed input gear 46A and the fourth-speed input gear 48A, respectively.

[0039] An even-numbered motor driven gear 51B is provided on the even-numbered intermediate shaft 43. The even-numbered motor driven gear 51B is formed to have a larger diameter than the fourth-speed input gear 48A, which is formed to have a larger diameter than the second-speed input gear 46A.

[0040] An even-numbered stage motor drive gear 51A is attached to the output shaft 24A of the even-numbered stage motor generator 24, and the even-numbered stage motor drive gear 51A meshes with an even-numbered stage motor driven gear 51B.

[0041] The even-numbered motor-generator 24 is disposed to the right of the even-numbered motor drive gear 51A in the axial direction of the input shaft 41. In other words, the even-numbered motor-generator 24 is disposed in the same axial position as the fourth-speed input gear 48A or the second-speed input gear 46A in the axial direction of the input shaft 41.

[0042] In this embodiment, the even-numbered motor drive gear 51A and the even-numbered motor driven gear 51B constitute a second rotating electrical gear pair. The even-numbered motor drive gear 51A constitutes a second drive gear, and the even-numbered motor driven gear 51B constitutes a second driven gear.

[0043] The even-stage motor drive gear 51A is formed with a smaller diameter than the even-stage motor driven gear 51B, and the rotational speed of the driving force transmitted from the even-stage motor generator 24 to the even-stage intermediate shaft 43 is reduced by the even-stage motor drive gear 51A and the even-stage motor driven gear 51B.

[0044] The second-speed output gear 46B is formed to have a larger diameter than the second-speed input gear 46A, and the fourth-speed output gear 48B is formed to have a smaller diameter than the fourth-speed input gear 48A.

[0045] The diameters of the input gears are formed to increase in the order of first speed input gear 45A, second speed input gear 46A, third speed input gear 47A, and fourth speed input gear 48A, and the diameters of the output gears are formed to decrease in the order of first speed output gear 45B, second speed output gear 46B, third speed output gear 47B, and fourth speed output gear 48B.

[0046] As a result, the gear ratio of 1st gear is the largest, and the gear ratios decrease in the order of 1st gear, 2nd gear, 3rd gear, and 4th gear. The gears of the transmission 3 in this embodiment are configured with four forward gears, but the total number of gears is not limited to four.

[0047] The first-speed input gear 45A and the third-speed input gear 47A constitute a first intermediate shaft side gear, the first-speed output gear 45B and the third-speed output gear 47B constitute a first output shaft side gear, the second-speed input gear 46A and the fourth-speed input gear 48A constitute a second intermediate shaft side gear, and the second-speed output gear 46B and the fourth-speed output gear 48B constitute a second output shaft side gear.

[0048] A ring-shaped first dog clutch 52 is provided on the input shaft 41. The first dog clutch 52 is installed between the odd-numbered stage intermediate shaft 42 and the even-numbered stage intermediate shaft 43 in the axial direction of the input shaft 41, and is movable in the axial direction of the input shaft 41 and rotatable integrally with the input shaft 41.

[0049] The first dog clutch 52 has a plurality of dog teeth 52A provided at the left end and a plurality of dog teeth 52B provided at the right end.

[0050] A plurality of dog teeth 42A are formed on the right end portion (the end portion on the first dog clutch 52 side) of the odd-stage intermediate shaft 42, and a plurality of dog teeth 43A are formed on the left end portion (the end portion on the first dog clutch 52 side) of the even-stage intermediate shaft 43.

[0051] The first dog clutch 52 is moved in the axial direction of the input shaft 41 by the actuator 25 .

[0052] When the actuator 25 moves the first dog clutch 52 from the neutral position toward the odd-stage intermediate shaft 42 and switches it to an odd-stage position where the dog teeth 52A mesh with the dog teeth 42A of the odd-stage intermediate shaft 42, the input shaft 41 is connected to the odd-stage intermediate shaft 42 via the first dog clutch 52.

[0053] As a result, the input shaft 41 and the odd-numbered stage intermediate shaft 42 rotate integrally, and the driving force of the engine 2 is transmitted from the input shaft 41 to the odd-numbered stage intermediate shaft 42. The odd-numbered stage position in this embodiment is the first position.

[0054] When the actuator 25 moves the first dog clutch 52 from the neutral position toward the even-stage intermediate shaft 43 and switches it to an even-stage position where the dog teeth 52B and the dog teeth 43A of the even-stage intermediate shaft 43 mesh with each other, the input shaft 41 is connected to the even-stage intermediate shaft 43 via the first dog clutch 52.

[0055] As a result, the input shaft 41 and the even-numbered intermediate shaft 43 rotate integrally, and the driving force of the engine 2 is transmitted from the input shaft 41 to the even-numbered intermediate shaft 43. The even-numbered position in this embodiment is the second position.

[0056] When the first dog clutch 52 is in a neutral position where it is not connected to the odd-numbered stage intermediate shaft 42 or the even-numbered stage intermediate shaft 43, the input shaft 41 rotates relative to the odd-numbered stage intermediate shaft 42 and the even-numbered stage intermediate shaft 43, and the driving force of the engine 2 is not transmitted to the odd-numbered stage intermediate shaft 42 or the even-numbered stage intermediate shaft 43.

[0057] The odd-numbered stage motor driven gear 50B is installed closest to the first dog clutch 52 in the axial direction of the odd-numbered stage intermediate shaft 42, and the first-speed input gear 45A and the third-speed input gear 47A are installed on the opposite side of the odd-numbered stage motor driven gear 50B from the first dog clutch 52.

[0058] In this embodiment, the odd-numbered motor driven gear 50B, the first-speed input gear 45A, and the third-speed input gear 47A are arranged so that their diameters gradually decrease as they move away from the first dog clutch 52 in the axial direction of the odd-numbered intermediate shaft 42.

[0059] The even-stage motor driven gear 51B is installed closest to the first dog clutch 52 in the axial direction of the even-stage intermediate shaft 43, and the second-speed input gear 46A and the fourth-speed input gear 48A are installed on the opposite side of the even-stage motor driven gear 51B from the first dog clutch 52.

[0060] In this embodiment, the even-numbered motor driven gear 51B, the second-speed input gear 46A, and the fourth-speed input gear 48A are arranged so that their diameters gradually decrease as they move away from the first dog clutch 52 in the axial direction of the even-numbered intermediate shaft 43.

[0061] The output shaft 44 is provided with a ring-shaped second dog clutch 53 and a ring-shaped third dog clutch 54, respectively.

[0062] The second dog clutch 53 is installed between the first-speed output gear 45B and the third-speed output gear 47B in the axial direction of the output shaft 44, and is freely movable in the axial direction of the output shaft 44 and is freely rotatable together with the output shaft 44.

[0063] The second dog clutch 53 has a plurality of dog teeth 53A provided at the left end and a plurality of dog teeth 53B provided at the right end.

[0064] A plurality of dog teeth 45G are formed on the right end of the first-speed output gear 45B, and a plurality of dog teeth 47G are formed on the left end of the third-speed output gear 47B.

[0065] The second dog clutch 53 is moved in the axial direction of the output shaft 44 by the actuator 25 .

[0066] When the actuator 25 moves the second dog clutch 53 from the neutral position toward the first-speed output gear 45B and the dog teeth 53A mesh with the dog teeth 45G of the first-speed output gear 45B, the first-speed output gear 45B is connected to the output shaft 44 via the second dog clutch 53.

[0067] As a result, the first-speed output gear 45B rotates integrally with the output shaft 44, and driving force can be transmitted between the odd-numbered intermediate shaft 42 and the output shaft 44 via the first-speed gear pair 45.

[0068] When the actuator 25 moves the second dog clutch 53 from the neutral position toward the third-speed output gear 47B and the dog teeth 53B mesh with the dog teeth 47G of the third-speed output gear 47B, the third-speed output gear 47B is connected to the output shaft 44 via the second dog clutch 53.

[0069] As a result, the third-speed output gear 47B rotates integrally with the output shaft 44, and driving force can be transmitted between the odd-numbered intermediate shaft 42 and the output shaft 44 via the third-speed gear pair 47.

[0070] The third dog clutch 54 is installed between the second-speed output gear 46B and the fourth-speed output gear 48B in the axial direction of the output shaft 44, and is freely movable in the axial direction of the output shaft 44 and is freely rotatable together with the output shaft 44.

[0071] The third dog clutch 54 has a plurality of dog teeth 54A provided at the right end and a plurality of dog teeth 54B provided at the left end.

[0072] A plurality of dog teeth 46G are formed on the left end of the second-speed output gear 46B, and a plurality of dog teeth 48G are formed on the right end of the fourth-speed output gear 48B.

[0073] The third dog clutch 54 is moved in the axial direction of the output shaft 44 by the actuator 25 .

[0074] When the actuator 25 moves the third dog clutch 54 from the neutral position toward the second-speed output gear 46B and the dog teeth 54A mesh with the dog teeth 46G of the second-speed output gear 46B, the second-speed output gear 46B is connected to the output shaft 44 via the third dog clutch 54.

[0075] As a result, the second-speed output gear 46B rotates integrally with the output shaft 44, and driving force can be transmitted between the even-numbered intermediate shaft 43 and the output shaft 44 via the second-speed gear pair 46.

[0076] When the actuator 25 moves the third dog clutch 54 from the neutral position toward the fourth-speed output gear 48B and the dog teeth 54B mesh with the dog teeth 48G of the fourth-speed output gear 48B, the fourth-speed output gear 48B is connected to the output shaft 44 via the third dog clutch 54.

[0077] As a result, the fourth-speed output gear 48B rotates integrally with the output shaft 44, and driving force can be transmitted between the even-numbered intermediate shaft 43 and the output shaft 44 via the fourth-speed gear pair 48.

[0078] That is, the transmission 3 of this embodiment can select either first or third gear between the odd-numbered intermediate shaft 42 and the output shaft 44, thereby establishing either first or third gear, and can select either second or fourth gear between the even-numbered intermediate shaft 43 and the output shaft 44, thereby establishing either second or fourth gear.

[0079] In the transmission 3 of this embodiment, when the gear is in first or third gear, the transmission path of the driving force of the engine 2 is a transmission path from the crankshaft 2S of the engine 2 to the output shaft 44 via the input shaft 41, the odd-numbered intermediate shaft 42, and the first-speed gear pair 45 or the third-speed gear pair 47.

[0080] When the gear is in second or fourth gear, the transmission path of the driving force of the engine 2 is a transmission path that transmits the driving force from the crankshaft 2S of the engine 2 to the output shaft 44 via the input shaft 41, the even-numbered intermediate shaft 43, the second-speed gear pair 46 or the fourth-speed gear pair 48.

[0081] When the gear is in first or third gear, the transmission path of the driving force of the odd-numbered motor generator 23 is a transmission path that transmits the driving force from the odd-numbered motor generator 23 to the output shaft 44 via the odd-numbered motor drive gear 50A, the odd-numbered motor driven gear 50B, the odd-numbered intermediate shaft 42, and the first-speed gear pair 45 or the third-speed gear pair 47.

[0082] When the gear is in second or fourth gear, the transmission path of the driving force of the even-numbered motor generator 24 is a transmission path that transmits the driving force from the even-numbered motor generator 24 to the output shaft 44 via the even-numbered motor drive gear 51A, the even-numbered motor driven gear 51B, the even-numbered intermediate shaft 43, and the second-speed gear pair 46 or the fourth-speed gear pair 48.

[0083] In this embodiment, the first dog clutch 52 constitutes a first switching member, the second dog clutch 53 constitutes a second switching member, and the third dog clutch 54 constitutes a third switching member.

[0084] As described above, by controlling the switching states of the second dog clutch 53 and the third dog clutch 54 and the driving forces of the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24, it is possible to drive the vehicle 1 using each speed gear pair (45, 46, 47, 48). For ease of explanation, unless otherwise specified, a gear stage refers to a gear stage of a transmission path that transmits the driving force of the engine 2, and a gear change refers to a change in the transmission path that transmits the driving force of the engine 2.

[0085] A final drive gear 55 is provided on the left end of the output shaft 44. The differential device 22 has a final driven gear 22A that meshes with the final drive gear 55, and a differential mechanism 22B attached to the final driven gear 22A.

[0086] Drive shafts 31L and 31R are connected to the differential mechanism 22B. The differential device 22 distributes the driving force of the engine 2 to the drive shafts 31L and 31R via the differential mechanism 22B and transmits the power to the drive wheels 4L and 4R.

[0087] The HCU10, ECU11, TCU12 and BMS13 are each composed of a computer unit having a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), flash memory for storing backup data, etc., input ports and output ports.

[0088] The ROMs of these computer units store various constants, various maps, and the like, as well as programs for causing the computer units to function as the HCU 10, ECU 11, TCU 12, and BMS 13, respectively.

[0089] That is, the CPU executes the programs stored in the ROM using the RAM as a work area, and these computer units function as the HCU 10, ECU 11, TCU 12, and BMS 13 in this embodiment, respectively.

[0090] The ECU 11 controls the intake air amount, fuel injection amount, injection timing, ignition timing, etc. of the engine 2 to control the engine torque based on the command from the HCU 10.

[0091] The TCU 12 controls the actuator 25 based on commands from the HCU 10, and moves the first dog clutch 52, the second dog clutch 53, and the third dog clutch 54 to a neutral position, a shift position where an odd-numbered gear stage is established, and a shift position where an even-numbered gear stage is established.

[0092] The BMS 13 monitors the state of the battery 16 and transmits information such as the remaining capacity (SOC: State Of Charge) of the battery 16 to the HCU 10 .

[0093] In response to a command from the HCU 10, the odd-numbered stage inverter 14 and the even-numbered stage inverter 15 convert the DC power supplied from the battery 16 into three-phase AC power and supply it to the even-numbered stage motor generator 24 and the odd-numbered stage motor generator 23 so as to produce a motor torque according to the command from the HCU 10, or convert the three-phase AC power generated by the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 into DC power to charge the battery 16.

[0094] The odd-numbered stage inverter 14 and the even-numbered stage inverter 15 transmit information on the rotational speeds (rotational speeds) of the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 to the HCU 10. The battery 16 is formed of, for example, a secondary battery such as a lithium ion battery.

[0095] The odd-stage motor generator 23 and the even-stage motor generator 24 function as electric motors that generate driving force for the vehicle 1 using power supplied from the battery 16 via the odd-stage inverter 14 and the even-stage inverter 15, and also function as generators that perform regenerative power generation using the rotational force (reverse driving force) input from the drive wheels 4L and 4R via the differential device 22.

[0096] In this embodiment, the odd-numbered stage motor generator 23 constitutes a first rotating electric machine, and the even-numbered stage motor generator 24 constitutes a second rotating electric machine.

[0097] 1, the HCU 10 is connected to a shift position sensor 56, an accelerator opening sensor 57, and a vehicle speed sensor 58. The shift position sensor 56 detects the shift position selected by the operation of a shift lever 59 by the driver.

[0098] The shift position can be selected from, for example, P range (parking position), N range (neutral position), R range (reverse driving position), D range (forward driving position), and B range (engine braking position). B range is a shift position that generates a stronger engine brake than D range.

[0099] The shift position sensor 56 transmits a signal to the HCU 10 according to the shift position selected by the driver.

[0100] The accelerator opening sensor 57 detects the opening of the accelerator pedal 60 operated by the driver (accelerator operation amount), and transmits a signal corresponding to the accelerator opening to the HCU 10. The vehicle speed sensor 58 detects the speed of the vehicle 1 (vehicle speed), and transmits a signal corresponding to the vehicle speed to the HCU 10.

[0101] The HCU 10 calculates the driving force required by the driver (driver required torque) based on the position of the shift lever 59 transmitted from the shift position sensor 56, the accelerator opening transmitted from the accelerator opening sensor 57, and the vehicle speed transmitted from the vehicle speed sensor 58, determines the EV mode or the HEV mode, and switches the driving mode of the vehicle 1 to the EV mode or the HEV mode.

[0102] The EV mode is a mode in which the vehicle travels using the odd-numbered stage motor generator 23 or the even-numbered stage motor generator 24 without using the driving force of the engine 2. The HEV mode is a mode in which the engine 2 is in an operating state in which the driving force of the engine 2 can be transmitted to the drive wheels (4L, 4R).

[0103] The HCU 10 issues commands to the ECU 11, the TCU 12, the odd-numbered inverter 14, and the even-numbered inverter 15 so that the remaining capacity of the battery 16 becomes the driver-requested torque within a predetermined range in the EV mode or the HEV mode.

[0104] Odd-numbered stage inverter 14 and even-numbered stage inverter 15 control the driving force (motor torque) of odd-numbered stage motor generator 23 and even-numbered stage motor generator 24 based on a command from HCU 10, and ECU 11 controls the engine torque based on a command from HCU 10.

[0105] The TCU 12 controls the actuator 25 based on a command from the HCU 10 to perform switching control of the first dog clutch 52, the second dog clutch 53, and the third dog clutch 54, thereby performing a gear change.

[0106] The EV mode is a driving mode in which the engine 2 is stopped and the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 satisfy the driver's requested torque to drive the vehicle 1.

[0107] In the EV mode, engine 2 is not operating, so the engine speed is maintained at zero.

[0108] The HEV mode is a driving mode in which the engine 2 is operated and the driver's requested torque is satisfied by at least the engine torque among the engine torque and the motor torque of the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24, and the vehicle 1 is driven.

[0109] In the HEV mode, the vehicle travels using only engine torque, or travels using both engine torque and motor torque (so-called motor assist).

[0110] When shifting from either an odd or even gear to the other odd or even gear, the HCU 10 controls the ECU 11 based on information transmitted from the shift position sensor 56, the accelerator opening sensor 57, and the vehicle speed sensor 58, thereby reducing the driving force of the engine 2 to a predetermined value.

[0111] The HCU 10 controls the ECU 11 to close the throttle valve that adjusts the amount of intake air to the engine 2, thereby reducing the driving force of the engine 2.

[0112] When reducing the driving force of the engine 2 to a predetermined value, the HCU 10 controls the odd-stage inverter 14 and the even-stage inverter 15 to increase the motor torque of the odd-stage motor generator 23 of the odd-stage intermediate shaft 42 having the first-speed gear pair 45 or the third-speed gear pair 47 in which the current gear stage is established, or the motor torque of the even-stage motor generator 24 of the even-stage intermediate shaft 43 having the second-speed gear pair 46 or the fourth-speed gear pair 48 in which the current gear stage is established, so as to supplement the driving force of the engine 2.

[0113] Next, the HCU 10 controls the ECU 11, the odd-numbered stage inverter 14, and the even-numbered stage inverter 15 to perform synchronization control of the rotation speed of the odd-numbered stage intermediate shaft 42 and the rotation speed of the input shaft 41, or the rotation speed of the even-numbered stage intermediate shaft 43 and the rotation speed of the input shaft 41, which are shifted from the current gear stage to the next gear stage.

[0114] Specifically, when the driving force of the engine 2 decreases to a predetermined value, the HCU 10 controls the TCU 12 to switch the first dog clutch 52 from either the odd-numbered gear position or the even-numbered gear position that establishes the current gear to the neutral position.

[0115] Next, the HCU 10 controls the ECU 11, the odd-stage inverter 14, and the even-stage inverter 15 to perform synchronization control of the rotation speed of the odd-stage intermediate shaft 42 or the even-stage intermediate shaft 43 corresponding to the next gear stage with the rotation speed of the input shaft 41.

[0116] When the rotation speed of the odd-numbered intermediate shaft 42 and the rotation speed of the input shaft 41, or the rotation speed of the even-numbered intermediate shaft 43 and the rotation speed of the input shaft 41, the HCU 10 controls the TCU 12 to switch the first dog clutch 52 from the neutral position to an odd-numbered position or an even-numbered position that establishes the next gear stage.

[0117] When shifting from odd to even gears, if the first dog clutch 52 is switched from the neutral position to the even gear position, the HCU 10 controls the ECU 11, the odd gear inverter 14, and the even gear inverter 15 to synchronize the rotation speed of the second-speed output gear 46B with the rotation speed of the output shaft 44, or synchronizes the rotation speed of the fourth-speed output gear 48B with the rotation speed of the output shaft 44, and once the rotation speeds are synchronized, the third dog clutch 54 connects the second-speed output gear 46B or the fourth-speed output gear 48B to the output shaft 44.

[0118] When shifting from an even gear to an odd gear, if the first dog clutch 52 is switched from the neutral position to the odd gear position, the HCU 10 controls the ECU 11, the odd gear inverter 14, and the even gear inverter 15 to synchronize the rotation speed of the first gear output gear 45B with the rotation speed of the output shaft 44, or synchronizes the rotation speed of the third gear output gear 47B with the rotation speed of the output shaft 44, and once these rotation speeds are synchronized, the second dog clutch 53 connects the first gear output gear 45B or the third gear output gear 47B to the output shaft 44.

[0119] Furthermore, when shifting from an odd gear to an even gear, the HCU 10 switches the third dog clutch 54 to the neutral position at the same timing as when the first dog clutch 52 is switched to the neutral position, and when shifting from an even gear to an odd gear, the HCU 10 switches the second dog clutch 53 to the neutral position at the same timing as when the first dog clutch 52 is switched to the neutral position.

[0120] The HCU 10 , ECU 11 , TCU 12 , odd-stage inverter 14 and even-stage inverter 15 of this embodiment constitute a control unit 30 .

[0121] Based on the driving modes shown in FIG. 3, the switching control of the first dog clutch 52, the second dog clutch 53, and the third dog clutch 54 in the EV mode and the HEV mode will be described.

[0122] 1) EV neutral mode This is the EV mode, and is the mode when the shift position of the shift lever 59 is in the N range or the P range. The first dog clutch 52, the second dog clutch 53, and the third dog clutch 54 are in the neutral position.

[0123] Therefore, the engine 2, odd-stage motor generator 23, and even-stage motor generator 24 are disconnected from the drive wheels 4L and 4R, and engine torque and motor torque are not transmitted from the engine 2, odd-stage motor generator 23, and even-stage motor generator 24 to the drive wheels 4L and 4R.

[0124] In the EV neutral mode, the second dog clutch 53 and the third dog clutch 54 are in the neutral position, but if the motor torque of the odd-stage motor generator 23 and the even-stage motor generator 24 is controlled to zero, the second dog clutch 53 and the third dog clutch 54 do not need to be in the neutral position.

[0125] 2) EV1-EV2 mode This is the EV mode, which is the mode when the shift position of the shift lever 59 is in the D range or the R range.

[0126] The first dog clutch 52 is switched to a neutral position, the second dog clutch 53 is switched to a position for establishing first gear, and the third dog clutch 54 is switched to a position for establishing second gear.

[0127] In the EV1-EV2 mode, when the vehicle 1 is traveling forward, the motor torque of the odd-numbered stage motor generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the first-speed gear pair 45, and the motor torque of the even-numbered stage motor generator 24 is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46, and the motor torque of the motor generators 23, 24 is transmitted to the drive wheels 4L, 4R.

[0128] On the other hand, when the vehicle 1 is traveling in reverse, the odd-numbered stage motor generators 23 and the even-numbered stage motor generators 24 rotate in the opposite direction to when the vehicle is traveling forward, and the motor torque of the odd-numbered stage motor generators 23 and the even-numbered stage motor generators 24 is transmitted to the drive wheels 4L, 4R via the same path as the drive force transmission path when the vehicle is traveling forward.

[0129] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L, 4R is transmitted from the differential device 22 to the output shaft 44.

[0130] The rotational force transmitted to the output shaft 44 is transmitted from the first gear pair 45 to the odd-numbered stage motor generator 23 via the odd-numbered stage intermediate shaft 42, and from the second gear pair 46 to the even-numbered stage motor generator 24 via the even-numbered stage intermediate shaft 43, thereby generating regenerative power in the motor generators 23 and 24.

[0131] 3) EV2 mode This is the EV mode, which is the mode when the shift position of the shift lever 59 is in the D range.

[0132] The first dog clutch 52 and the second dog clutch 53 are switched to the neutral position, and the third dog clutch 54 is switched to a position that establishes the second speed.

[0133] In EV2 mode, when the vehicle 1 is traveling forward, the motor torque of the even-numbered motor generator 24 is transmitted from the even-numbered intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46, and the motor torque of the even-numbered motor generator 24 is transmitted to the drive wheels 4L and 4R.

[0134] The EV2 mode is temporarily implemented when switching from the EV1-EV2 mode to the EV2-EV3 mode, and the drive wheels 4L and 4R are driven by the motor torque of the even-numbered motor generator 24 while the gear shift is being switched from 1st gear to 3rd gear.

[0135] 4) EV2-EV3 mode This is the EV mode, which is the mode when the shift position of the shift lever 59 is in the D range.

[0136] The first dog clutch 52 is switched to a neutral position, the second dog clutch 53 is switched to a position for establishing the third speed, and the third dog clutch 54 is switched to a position for establishing the second speed.

[0137] In the EV2-EV3 mode, when the vehicle 1 is traveling forward, the motor torque of the odd-numbered stage motor generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47, and the motor torque of the even-numbered stage motor generator 24 is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46, and the motor torque of the motor generators 23, 24 is transmitted to the drive wheels 4L, 4R.

[0138] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L, 4R is transmitted from the differential device 22 to the output shaft 44.

[0139] The rotational force transmitted to the output shaft 44 is transmitted from the third-speed gear pair 47 to the odd-numbered motor-generator 23 via the odd-numbered intermediate shaft 42, and from the second-speed gear pair 46 to the even-numbered motor-generator 24 via the even-numbered intermediate shaft 43, thereby generating regenerative power in the motor-generators 23 and 24.

[0140] The EV2-EV3 mode is not implemented in the R range because there is no need to increase the vehicle speed when vehicle 1 is traveling in reverse.

[0141] 5) EV3 mode This is the EV mode, which is the mode when the shift position of the shift lever 59 is in the D range.

[0142] The first dog clutch 52 and the third dog clutch 54 are switched to the neutral position, and the second dog clutch 53 is switched to a position that establishes the third speed.

[0143] In EV3 mode, when the vehicle 1 is traveling forward, the motor torque of the odd-numbered motor generator 23 is transmitted to the output shaft 44 via the third gear pair 47, and the motor torque of the odd-numbered motor generator 23 is transmitted to the drive wheels 4L, 4R.

[0144] The EV3 mode is temporarily implemented when switching from the EV2-EV3 mode to the EV3-EV4 mode, and the drive wheels 4L and 4R are driven by the motor torque of the odd-numbered stage motor generator 23 while the gear stage is being switched from the second stage to the fourth stage.

[0145] 6) EV3-EV4 mode This is the EV mode, which is the mode when the shift position of the shift lever 59 is in the D range.

[0146] The first dog clutch 52 is switched to a neutral position, the second dog clutch 53 is switched to a position for establishing the third gear, and the third dog clutch 54 is switched to a position for establishing the fourth gear.

[0147] In the EV3-EV4 mode, when the vehicle 1 is traveling forward, the motor torque of the odd-numbered stage motor generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47, and the motor torque of the even-numbered stage motor generator 24 is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the fourth-speed gear pair 48, and the motor torque of the motor generators 23, 24 is transmitted to the drive wheels 4L, 4R.

[0148] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L, 4R is transmitted from the differential device 22 to the output shaft 44.

[0149] The rotational force transmitted to the output shaft 44 is transmitted from the third-speed gear pair 47 to the odd-speed motor-generator 23 via the odd-speed intermediate shaft 42, and from the fourth-speed gear pair 48 to the even-speed motor-generator 24 via the even-speed intermediate shaft 43, thereby generating regenerative power in the motor-generators 23 and 24.

[0150] The EV3-EV4 mode is not implemented in the R range because there is no need to increase the vehicle speed when vehicle 1 is traveling in reverse.

[0151] 7) HEV neutral mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the N range or P range.

[0152] The first dog clutch 52, the second dog clutch 53 and the third dog clutch 54 are in the neutral position.

[0153] Therefore, the engine 2, odd-stage motor generator 23, and even-stage motor generator 24 are disconnected from the drive wheels 4L and 4R, and engine torque and motor torque are not transmitted from the engine 2, odd-stage motor generator 23, and even-stage motor generator 24 to the drive wheels 4L and 4R.

[0154] In the HEV neutral mode, the second dog clutch 53 and the third dog clutch 54 are in the neutral position, but if the motor torque of the odd-stage motor generator 23 and the even-stage motor generator 24 is controlled to zero, the second dog clutch 53 and the third dog clutch 54 do not need to be in the neutral position.

[0155] 8) HEV neutral power generation mode The vehicle is in the HEV mode, the shift lever 59 is in the N or P range, and the motor is generating electricity.

[0156] The first dog clutch 52 is in an even-numbered stage position, and the second dog clutch 53 and the third dog clutch 54 are in a neutral position.

[0157] In the HEV neutral power generation mode, the input shaft 41 is connected to the even-stage intermediate shaft 43 by the first dog clutch 52, and engine torque is transmitted from the input shaft 41 to the even-stage motor generator 24 via the even-stage intermediate shaft 43, causing the even-stage motor generator 24 to generate power.

[0158] In the HEV neutral power generation mode, the second dog clutch 53 and the third dog clutch 54 are in the neutral position, but if the motor torque of the odd-stage motor generator 23 is controlled to zero, the second dog clutch 53 does not need to be in the neutral position.

[0159] 9) HEV1-EV1-EV2 mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the D range.

[0160] The first dog clutch 52 is switched to an odd-numbered gear position, the second dog clutch 53 is switched to a position for establishing first gear, and the third dog clutch 54 is switched to a position for establishing second gear.

[0161] In the HEV1-EV1-EV2 mode, when the vehicle 1 is traveling forward, the input shaft 41 is connected to the odd-numbered stage intermediate shaft 42.

[0162] As a result, the engine torque and the motor torque of the odd-numbered stage motor-generator 23 are transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the first-speed gear pair 45, and the motor torque of the even-numbered stage motor-generator 24 is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46.

[0163] As a result, the drive wheels 4L, 4R are driven by at least the engine 2 and the odd-numbered stage motor generator 23. When assisting the engine 2, both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 are driven.

[0164] When the odd-numbered stage motor-generator 23 generates electricity using the engine torque available during running, the engine torque is transmitted from the odd-numbered stage intermediate shaft 42 to the odd-numbered stage motor-generator 23. When the even-numbered stage motor-generator 24 generates electricity using the engine torque available during running, the engine torque is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the first-speed gear pair 45, and then to the even-numbered stage motor-generator 24 via the second-speed gear pair 46 and the even-numbered stage intermediate shaft 43.

[0165] During regenerative power generation by the odd-numbered stage motor-generators 23 and the even-numbered stage motor-generators 24, power is transmitted from the output shaft 44 via the first-speed gear pair 45 to the odd-numbered stage intermediate shaft 42 to the odd-numbered stage motor-generator 23, and from the output shaft 44 via the second-speed gear pair 46 and the even-numbered stage intermediate shaft 43 to the even-numbered stage motor-generator 24.

[0166] 10) HEV2-EV1-EV2 mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the D range.

[0167] The first dog clutch 52 is switched to an even-numbered gear position, the second dog clutch 53 is switched to a position for establishing first gear, and the third dog clutch 54 is switched to a position for establishing second gear.

[0168] In the HEV2-EV1-EV2 mode, the input shaft 41 is connected to the even-numbered intermediate shaft 43 when the vehicle 1 is traveling forward.

[0169] As a result, the engine torque and the motor torque of the even-numbered stage motor-generator 24 are transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46, and the motor torque of the odd-numbered stage motor-generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the first-speed gear pair 45.

[0170] As a result, the drive wheels 4L, 4R are driven by at least the engine 2 and the even-numbered stage motor generator 24. When assisting the engine 2, both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 are driven.

[0171] When the even-numbered stage motor-generators 24 generate electricity using the engine torque that is available while the vehicle is running, the engine torque is transmitted from the even-numbered stage intermediate shaft 43 to the even-numbered stage motor-generators 24. When the odd-numbered stage motor-generators 23 generate electricity using the engine torque that is available while the vehicle is running, the engine torque is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46, and then from the output shaft 44 to the odd-numbered stage motor-generators 23 via the first-speed gear pair 45 and the odd-numbered stage intermediate shaft 42.

[0172] Note that the regenerative power generation of the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 is the same as that in the HEV1-EV1-EV2 mode.

[0173] 11) HEV2-EV3-EV2 mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the D range.

[0174] The first dog clutch 52 is switched to an even-numbered gear position, the second dog clutch 53 is switched to a position for establishing the third gear, and the third dog clutch 54 is switched to a position for establishing the second gear.

[0175] In the HEV2-EV3-EV2 mode, the input shaft 41 is connected to the even-numbered intermediate shaft 43 when the vehicle 1 is traveling forward.

[0176] As a result, the engine torque and the motor torque of the even-numbered stage motor-generator 24 are transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46, and the motor torque of the odd-numbered stage motor-generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47.

[0177] When assisting the engine 2, both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 are driven.

[0178] Electricity generation using a portion of the engine torque is performed by only the even-numbered stage motor generator 24, or by both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24.

[0179] 12) HEV3-EV3-EV2 mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the D range.

[0180] The first dog clutch 52 is switched to an odd-numbered gear position, the second dog clutch 53 is switched to a position for establishing the third gear, and the third dog clutch 54 is switched to a position for establishing the second gear.

[0181] In the HEV3-EV3-EV2 mode, when the vehicle 1 is traveling forward, the input shaft 41 is connected to the odd-numbered stage intermediate shaft 42.

[0182] As a result, the engine torque and the motor torque of the odd-numbered stage motor-generator 23 are transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47, and the motor torque of the even-numbered stage motor-generator 24 is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46.

[0183] When assisting the engine 2, both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 are driven.

[0184] Electricity generation using a portion of the engine torque is performed by only the odd-numbered stage motor generator 23 or by both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24.

[0185] 13) HEV3-EV3-EV4 mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the D range.

[0186] The first dog clutch 52 is switched to an odd-numbered gear position, the second dog clutch 53 is switched to a position for establishing the third gear, and the third dog clutch 54 is switched to a position for establishing the fourth gear.

[0187] In the HEV3-EV3-EV4 mode, when the vehicle 1 is traveling forward, the input shaft 41 is connected to the odd-numbered stage intermediate shaft 42.

[0188] As a result, the engine torque and the motor torque of the odd-numbered stage motor-generator 23 are transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47, and the motor torque of the even-numbered stage motor-generator 24 is transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the fourth-speed gear pair 47.

[0189] When assisting the engine 2, both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 are driven.

[0190] Electricity generation using a portion of the engine torque is performed by only the odd-numbered stage motor generator 23 or by both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24.

[0191] 14) HEV4-EV3-EV4 mode This is the HEV mode, and is the mode when the shift position of the shift lever 59 is in the D range.

[0192] The first dog clutch 52 is switched to an even-numbered gear position, the second dog clutch 53 is switched to a position for establishing the third gear, and the third dog clutch 54 is switched to a position for establishing the fourth gear.

[0193] In the HEV4-EV3-EV4 mode, the input shaft 41 is connected to the even-numbered intermediate shaft 43 when the vehicle 1 is traveling forward.

[0194] As a result, the engine torque and the motor torque of the even-numbered stage motor-generator 24 are transmitted from the even-numbered stage intermediate shaft 43 to the output shaft 44 via the fourth-speed gear pair 47, and the motor torque of the odd-numbered stage motor-generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47.

[0195] When assisting the engine 2, both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24 are driven.

[0196] Electricity generation using a portion of the engine torque is performed by only the even-numbered stage motor generator 24, or by both the odd-numbered stage motor generator 23 and the even-numbered stage motor generator 24.

[0197] 15) EV1 series mode This is the HEV mode, which is the mode when the shift position of the shift lever 59 is in the D range or the R range. In this mode, the motor torque of the odd-numbered motor generator 23 is transmitted to the output shaft 44 via the first gear pair 45, causing the vehicle 1 to travel. In this mode, the engine torque is transmitted to the even-numbered motor generator 24 via the even-numbered intermediate shaft 43, causing the even-numbered motor generator 24 to generate electricity.

[0198] The first dog clutch 52 is in an even-numbered gear position, the second dog clutch 53 is in a position for establishing first gear, and the third dog clutch 54 is in a neutral position.

[0199] In the EV1 series mode, when the vehicle 1 is traveling forward, the motor torque of the odd-numbered stage motor generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the first-speed gear pair 45.

[0200] On the other hand, when the vehicle 1 is traveling backward, the odd-numbered motor generator 23 rotates in the opposite direction to when the vehicle 1 is traveling forward, and the motor torque of the odd-numbered motor generator 23 is transmitted to the output shaft 44 via the first gear pair 45.

[0201] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L, 4R is transmitted from the differential device 22 to the odd-numbered motor-generator 23 via the output shaft 44, the first-speed gear pair 45 and the odd-numbered intermediate shaft 42, and regenerative power generation is performed by the odd-numbered motor-generator 23.

[0202] When the even-numbered stage motor generator 24 generates power, engine torque is transmitted from the input shaft 41 to the even-numbered stage motor generator 24 via the even-numbered stage intermediate shaft 43 .

[0203] The EV1 series mode is mainly used when starting in D range in HEV mode, or when reversing in R range in HEV mode.

[0204] The EV1 series mode is also implemented as a mode that temporarily starts the engine 2 when transitioning from the EV1-EV2 mode in the EV mode to the HEV2-EV1-EV2 mode in the HEV mode.

[0205] 16) EV2 series mode This is the HEV mode, which is the mode when the shift lever 59 is in the D range. In this mode, the vehicle 1 runs using the even-numbered motor generator 24, and the odd-numbered motor generator 23 generates electricity using engine torque.

[0206] The first dog clutch 52 is switched to an odd-numbered gear position, the second dog clutch 53 is switched to a neutral position, and the third dog clutch 54 is switched to a position that establishes the second gear.

[0207] In the EV2 series mode, when the vehicle 1 is traveling forward, the motor torque of the even-numbered motor generator 24 is transmitted from the even-numbered intermediate shaft 43 to the output shaft 44 via the second-speed gear pair 46 .

[0208] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L, 4R is transmitted from the differential device 22 to the even-stage motor generator 24 via the output shaft 44, the second-speed gear pair 46, and the even-stage intermediate shaft 43, and regenerative power generation is performed by the even-stage motor generator 24.

[0209] When the odd-numbered stage motor generator 23 generates power, engine torque is transmitted from the input shaft 41 to the odd-numbered stage motor generator 23 via the odd-numbered stage intermediate shaft 42 .

[0210] The EV2 series mode is also used as a temporary mode to start engine 2 when transitioning from EV1-EV2 mode in EV mode to HEV1-EV1-EV2 mode in HEV mode or HEV3-EV3-EV2 mode in HEV mode.

[0211] 17) EV3 Series Mode This is the HEV mode, which is the mode when the shift lever 59 is in the D range. In this mode, the vehicle 1 runs using the odd-numbered motor generator 23, and the even-numbered motor generator 24 generates electricity using engine torque.

[0212] The first dog clutch 52 is in an even-numbered gear position, the second dog clutch 53 is in a position for establishing the third gear, and the third dog clutch 54 is in a neutral position.

[0213] In the EV3 series mode, when the vehicle 1 is traveling forward, the motor torque of the odd-numbered stage motor generator 23 is transmitted from the odd-numbered stage intermediate shaft 42 to the output shaft 44 via the third-speed gear pair 47.

[0214] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L and 4R is transmitted from the differential device 22 to the odd-numbered stage motor generator 23 via the output shaft 44, the third-speed gear pair 47, and the odd-numbered stage intermediate shaft 42, and regenerative power generation is performed by the odd-numbered stage motor generator 23.

[0215] When the even-numbered stage motor generator 24 generates power, engine torque is transmitted from the input shaft 41 to the even-numbered stage motor generator 24 via the even-numbered stage intermediate shaft 43 .

[0216] The EV3 series mode is also used as a temporary mode to start engine 2 when transitioning from EV2-EV3 mode in EV mode to HEV2-EV3-EV2 mode in HEV mode or HEV4-EV3-EV4 mode in HEV mode.

[0217] 18) EV4 series mode This is the HEV mode, which is the mode when the shift lever 59 is in the D range. In this mode, the vehicle 1 runs using the even-numbered motor generator 24, and the odd-numbered motor generator 23 generates electricity using engine torque.

[0218] The first dog clutch 52 is switched to an odd-numbered gear position, the second dog clutch 53 is switched to a neutral position, and the third dog clutch 54 is switched to a position that establishes the fourth gear.

[0219] In the EV4 series mode, when the vehicle 1 is traveling forward, the motor torque of the even-numbered motor generator 24 is transmitted from the even-numbered intermediate shaft 43 to the output shaft 44 via the fourth-speed gear pair 48.

[0220] When the vehicle 1 decelerates, the rotational force of the drive wheels 4L, 4R is transmitted from the differential device 22 to the even-stage motor generator 24 via the output shaft 44, the fourth-speed gear pair 48, and the even-stage intermediate shaft 43, and regenerative power generation is performed by the even-stage motor generator 24.

[0221] When the odd-numbered stage motor generator 23 generates power, engine torque is transmitted from the input shaft 41 to the odd-numbered stage motor generator 23 via the odd-numbered stage intermediate shaft 42 .

[0222] The EV4 series mode is also implemented as a mode that temporarily starts the engine 2 when transitioning from the EV3-EV4 mode in the EV mode to the HEV3-EV3-EV4 mode in the HEV mode.

[0223] The shift control executed by the control unit 30 of the engine 2 and transmission 3 configured as above will be described with reference to the timing chart of FIG. The timing chart of FIG. 4 is a timing chart of the shift control when shifting from 1st gear to 2nd gear in the HEV mode.

[0224] In the timing chart of FIG. 4, from top to bottom, the following are shown: rotation speed (rotation speeds (rotational speeds) of the engine 2, odd-numbered stage motor generator 23 (denoted by MG1), and even-numbered stage motor generator 24 (denoted by MG2)), vehicle speed, torque (driver requested torque, engine torque, motor torque), switching position of the first dog clutch 52, switching position of the second dog clutch 53, and switching position of the third dog clutch 54, and the horizontal axis represents the passage of time. Note that the rotation speeds indicate a state of change, and do not indicate specific values.

[0225] In the timing chart of Fig. 4, the vehicle speed and driver requested torque are indicated by solid lines, and the engine speed and engine torque are indicated by dashed lines. Also, in the timing chart of Fig. 4, the rotation speed and motor torque of odd-numbered stage motor-generator 23 are indicated by dashed lines, and the rotation speed and motor torque of even-numbered stage motor-generator 24 are indicated by dashed lines.

[0226] At time t0, the vehicle 1 is traveling at low speed in first gear in HEV mode. At this time, the first dog clutch 52 is in an odd-numbered gear position, the second dog clutch 53 is switched to a position that establishes first gear, and the third dog clutch 54 is switched to a position that establishes second gear, and the traveling mode is HEV1-EV1-EV2 mode.

[0227] At this time, the driving force of the engine 2 is transmitted from the odd-numbered intermediate shaft 42 to the driving wheels 4L, 4R via the first-speed gear pair 45. In addition, the driving force of the odd-numbered motor generator 23 can be transmitted to the driving wheels 4L, 4R via the first-speed gear pair 45, and the driving force of the even-numbered motor generator 24 can be transmitted to the driving wheels 4L, 4R via the second-speed gear pair 46.

[0228] When the driver depresses the accelerator pedal 60 at time t1, the driving force of the engine 2 increases, causing the rotation speed of the engine 2 and the vehicle speed to increase. In other words, the vehicle 1 accelerates. After the vehicle 1 has accelerated, a gear change starts at time t2. In other words, the HCU 10 issues a command to the ECU 11 to start the transition to the HEV2-EV1-EV2 mode.

[0229] At time t2, the ECU 11 controls the torque of the engine 2 based on a command from the HCU 10, and reduces the engine torque to approach zero.

[0230] At the same time as starting to reduce the torque of the engine 2, the HCU 10 issues a command to the odd-numbered stage inverter 14, causing the odd-numbered stage inverter 14 to increase the motor torque of the odd-numbered stage motor generator 23, thereby compensating for the reduction in engine torque. In other words, the motor torque is increased by the amount of the reduction in engine torque.

[0231] When the engine torque becomes zero (time t3), the HCU 10 commands the TCU 12 to switch the first dog clutch 52 from the odd-numbered gear position to the neutral position. At the same time, the HCU 10 commands the TCU 12 to switch the third dog clutch 54 from the position where the second gear is established to the neutral position.

[0232] When the first dog clutch 52 is switched from the odd-numbered gear position to the neutral position, the engine torque is zero, so that the first dog clutch 52 can be smoothly switched from the odd-numbered gear position to the neutral position.

[0233] Similarly, when the third dog clutch 54 is switched from the position where the second gear is established to the neutral position, the driving force acting on the output shaft 44 of the even-numbered motor generator 24 is set to zero, so that the third dog clutch 54 can be smoothly switched from the position where the second gear is established to the neutral position.

[0234] The predetermined value of the driving force of the engine 2 is zero. However, this predetermined value is not limited to zero, and may be a value close to zero.

[0235] After the third dog clutch 54 is switched to the neutral position, the HCU 10 issues a command to the even-stage inverter 15 to control the motor torque of the even-stage inverter 15 so that the rotation speed (rotational speed) of the input shaft 41 and the rotation speed (rotational speed) of the even-stage intermediate shaft 43 match (synchronize).

[0236] At this time, the rotation speed of the input shaft 41 is controlled by the engine torque, and the rotation speed of the even-numbered intermediate shaft 43 is controlled by the motor torque of the even-numbered motor generator 24 .

[0237] Here, since the torque response of the motor generator is higher than the torque response of the engine 2, the motor torque of the even-stage motor generator 24 is controlled to bring the rotation speed of the even-stage motor generator 24 closer to the rotation speed of the engine 2, i.e., the rotation speed of the input shaft 41, thereby performing control to synchronize the rotation speed of the input shaft 41 and the rotation speed of the even-stage intermediate shaft 43.

[0238] Specifically, the even-numbered intermediate shaft 43, which has been rotating at the second gear ratio, is driven to rotate by the even-numbered motor generator 24, thereby increasing the rotation speed of the even-numbered intermediate shaft 43.

[0239] This allows the rotation speed of the input shaft 41 and the rotation speed of the even-numbered intermediate shaft 43 to be synchronized in a short time.

[0240] The input shaft 41 is coaxially arranged and connected to the crankshaft 2S of the engine 2, and the rotation speed of the input shaft 41 is the same as the rotation speed of the engine 2. The HCU 10 detects the rotation speed of the engine 2 based on detection information from a crank angle sensor 61 (see FIG. 1) that detects the rotation speed of the crankshaft 2S of the engine 2.

[0241] Furthermore, the rotation speed of the even-numbered intermediate shaft 43 can be calculated from the rotation speed of the even-numbered motor generator 24. Specifically, the driving force of the even-numbered motor generator 24 is reduced by the even-numbered motor drive gear 51A and the even-numbered motor driven gear 51B and then transmitted to the even-numbered intermediate shaft 43.

[0242] As a result, the rotation speed of the even-numbered intermediate shaft 43 can be calculated from the rotation speed of the even-numbered motor generator 24 and the reduction ratio (gear ratio) of the even-numbered motor drive gear 51A and the even-numbered motor driven gear 51B.

[0243] Similarly, the rotation speed of the odd-numbered intermediate shaft 42 can be calculated from the rotation speed of the odd-numbered motor generator 23 and the reduction ratio of the odd-numbered motor drive gear 50A and the odd-numbered motor driven gear 50B.

[0244] When the rotation speed of the input shaft 41 and the rotation speed of the even-numbered intermediate shaft 43 are synchronized (time t4), the HCU 10 issues a command to the TCU 12 to switch the first dog clutch 52 from the neutral position to the even-numbered position.

[0245] Next, in order to mesh the dog teeth 54A of the third dog clutch 54 with the dog teeth 46G of the second-speed output gear 46B, the HCU 10 issues a command to the even-stage inverter 15 so that the rotation speed of the output shaft 44 is synchronized with the rotation speed of the second-speed output gear 46B, thereby controlling the motor torque of the even-stage motor generator 24, which has a higher torque responsiveness than the engine 2.

[0246] Specifically, the rotation speed of the even-numbered intermediate shaft 43, which rotates integrally in synchronization with the rotation speed of the input shaft 41, is reduced by the even-numbered motor-generator 24, thereby synchronizing the even-numbered intermediate shaft 43 with the output shaft 44.

[0247] Here, the rotation speed of the output shaft 44 is controlled by the motor torque of the odd-numbered motor-generator 23. The rotation speed of the second-speed output gear 46B is controlled by the engine torque and the motor torque of the even-numbered motor-generator 24.

[0248] From time t2, the driving force of the odd-numbered motor generator 23 is transmitted from the odd-numbered intermediate shaft 42 to the output shaft 44 via the first gear pair 45, and the acceleration of the vehicle 1 continues without interruption.

[0249] In this state, the rotation speed of the output shaft 44, the rotation speed of the first gear pair 45, and the rotation speed of the third gear pair 47 can be calculated from the rotation speed of the odd-numbered motor generator 23, the reduction ratio of the odd-numbered motor drive gear 50A and the odd-numbered motor driven gear 50B, and the gear ratio (gear ratio) of the first gear pair 45 and the third gear pair 47.

[0250] Further, the driving force of the even-numbered motor generator 24 is transmitted from the even-numbered intermediate shaft 43 to the second gear pair 46 or the fourth gear pair 48 .

[0251] As a result, the rotation speed of the second-speed output gear 46B and the rotation speed of the fourth-speed output gear 48B can be calculated from the rotation speed of the even-speed motor generator 24, the reduction ratio of the even-speed motor drive gear 51A and the even-speed motor driven gear 51B, and the gear ratio (gear ratio) of the second-speed gear pair 46 and the fourth-speed gear pair 48.

[0252] When the rotation speed of the output shaft 44 and the rotation speed of the second-speed output gear 46B match (time t5), the HCU 10 switches the third dog clutch 54 to the second-speed output gear 46B side and connects the second-speed output gear 46B to the output shaft 44.

[0253] This allows the driving force of the engine 2 and the driving force of the even-numbered motor-generator 24 to act on the output shaft 44. In other words, when considered in terms of the driving force transmission path of the engine 2, the state of the transmission 3 is one in which the shift from first gear to second gear is complete.

[0254] That is, at time t5, the odd-numbered motor-generator 23 transmits driving force from the odd-numbered intermediate shaft 42 to the output shaft 44 via the first-speed gear pair 45, which has a large gear ratio, so the rotation speed of the odd-numbered motor-generator 23 is greater than the rotation speed of the even-numbered motor-generator 24. Then, the rotation speed of the output shaft 44 and the rotation speed of the second-speed output gear 46B match.

[0255] Regarding the driving force transmission path of the engine 2, when the shift from first gear to second gear is completed, the first dog clutch 52 is switched to the even-numbered gear position, the second dog clutch 53 is switched to the position that establishes first gear, and the third dog clutch 54 is switched to the position that establishes second gear, so that the driving force of the engine 2 is transmitted from the even-numbered gear intermediate shaft 43 to the driving wheels 4L and 4R via the second-speed gear pair 46.

[0256] Furthermore, when the shift from first gear to second gear is completed (time t5), HCU 10 issues a command to ECU 11 to start control of HEV2-EV1-EV2 mode, and ECU 11 controls to increase the driving force of the engine. Furthermore, HCU 10 issues a command to odd-numbered stage inverter 14 and even-numbered stage inverter 15 to reduce the motor torque of odd-numbered stage motor generator 23 and even-numbered stage motor generator 24. This completes the transition to HEV2-EV1-EV2 mode.

[0257] Here, first-speed gear pair 45 has a larger gear ratio than third-speed gear pair 47. For this reason, if first-speed output gear 45B is kept connected to output shaft 44 by second dog clutch 53 after completion of the gear shift from first speed to second speed, the rotation speed of odd-speed motor generator 23 and odd-speed intermediate shaft 42 when motor torque is transmitted to drive wheels 4L, 4R via first-speed gear pair 45 during motor assist by odd-speed motor generator 23 will be higher than the rotation speed when motor torque is transmitted via third-speed gear pair 47.

[0258] Therefore, the loss of the odd-numbered stage motor generator 23 when passing through the first gear pair 45 during motor assist is greater than the loss of the odd-numbered stage motor generator 23 when passing through the third gear pair 47 .

[0259] For this reason, the HCU 10 performs a process for reducing the loss of the odd-numbered stage motor-generator 23.

[0260] Specifically, from time t5, the vehicle 1 accelerates further, and the rotation speed of the odd-stage intermediate shaft 42 etc. increases, and when it reaches a predetermined rotation speed (threshold) (time t6), the HCU 10 starts the transition to the HEV2-EV3-EV2 mode and controls the TCU 12 to switch the second dog clutch 53 from the first gear side to the neutral position.

[0261] 4, the motor torque of the odd-numbered stage motor-generator 23 is reduced before time t6 (before reaching the threshold value), so the second dog clutch 53 can be easily switched from the first speed side to the neutral position. Note that if the odd-numbered stage motor-generator 23 is generating torque for motor assist or power generation at time t6, the HCU 10 issues a command to the odd-numbered stage inverter 14 to reduce the motor torque of the odd-numbered stage motor-generator 23.

[0262] Next, in order to bring the dog teeth 53B of the second dog clutch 53 into mesh with the dog teeth 47G of the third-speed output gear 47B, the HCU 10 issues a command to the odd-numbered stage motor generator 23 so that the rotation speed of the third-speed output gear 47B matches the rotation speed of the output shaft 44, thereby controlling the motor torque of the odd-numbered stage motor generator 23. Specifically, the rotation speed of the odd-numbered stage intermediate shaft 42, which is rotating at high speed via the first-speed gear pair 45, is reduced by the odd-numbered stage motor generator 23, so that the rotation speed of the third-speed output gear 47B is synchronized with that of the output shaft 44.

[0263] When the rotation speed of the output shaft 44 and the rotation speed of the third-speed output gear 47B match (time t7), the HCU 10 switches the second dog clutch 53 to the third-speed output gear 47B side and connects the third-speed output gear 47B to the output shaft 44.

[0264] Between time t6 and time t7, driving force cannot be transmitted via the odd-numbered intermediate shaft 42, but at this time, the first dog clutch 52 is switched to the even-numbered position and the third dog clutch 54 is switched to a position that establishes second gear, so the driving force of the engine 2 is transmitted from the even-numbered intermediate shaft 43 to the driving wheels 4L, 4R via the second gear pair 46, and the vehicle 1 can continue accelerating.

[0265] In other words, the driving force transmission path through which engine torque is transmitted from the engine 2 to the drive wheels 4L, 4R is maintained in the second gear position.

[0266] In this way, the transition from the HEV1-EV1-EV2 mode to the HEV2-EV3-EV2 mode is completed.

[0267] Similar shift control is performed for transitions from HEV2-EV3-EV2 mode to HEV3-EV3-EV2 mode, and from HEV3-EV3-EV2 mode to HEV3-EV3-EV4 mode, i.e., transitions from 2nd gear to 3rd gear, and transitions from HEV3-EV3-EV4 mode to HEV4-EV3-EV4 mode, i.e., transitions from 3rd gear to 4th gear, so explanations will be omitted.

[0268] As described above, the transmission 3 of the vehicle 1 of this embodiment includes an input shaft 41 to which the driving force of the engine 2 is transmitted, an odd-numbered stage intermediate shaft 42 that is arranged coaxially with the input shaft 41 and is rotatable relative to the input shaft 41, an even-numbered stage intermediate shaft 43 that is arranged coaxially with the input shaft 41 and opposite the odd-numbered stage intermediate shaft 42 in the axial direction of the input shaft and is rotatable relative to the input shaft 41, and an output shaft 44 that is arranged parallel to the odd-numbered stage intermediate shaft 42 and the even-numbered stage intermediate shaft 43 and transmits the driving force to the drive wheels 4L, 4R.

[0269] The transmission 3 also includes an odd-numbered stage motor generator 23 connected to the odd-numbered stage intermediate shaft 42 so as to be able to transmit driving force, and an even-numbered stage motor generator 24 connected to the even-numbered stage intermediate shaft 43 so as to be able to transmit driving force.

[0270] The transmission 3 also includes a first gear pair 45 and a third gear pair 47 that connect the odd-numbered intermediate shaft 42 and the output shaft 44 so as to be able to transmit driving force, and have different gear ratios, and a second gear pair 46 and a fourth gear pair 48 that connect the even-numbered intermediate shaft 43 and the output shaft 44 so as to be able to transmit driving force, and have different gear ratios.

[0271] In addition, it is provided with a first dog clutch 52 that can be switched between a neutral position, an odd-numbered stage position that connects the input shaft 41 and the odd-numbered stage intermediate shaft 42, and an even-numbered stage position that connects the input shaft 41 and the even-numbered stage intermediate shaft 43.

[0272] This allows for smooth gear changes without using multiple clutches as in a dual clutch system, making it possible to reduce the size of the transmission 3 and the manufacturing costs of the transmission 3.

[0273] Furthermore, when shifting from an odd number stage to an even number stage, the engine torque is supplemented by the motor torque of the odd number stage motor generator 23, and when shifting from an even number stage to an odd number stage, the engine torque is supplemented by the motor torque of the even number stage motor generator 24, so that torque loss during shifting can be prevented, and a decrease in the acceleration performance of the vehicle 1 and a feeling of discomfort to the driver when accelerating the vehicle 1 can be prevented.

[0274] Furthermore, by performing synchronization control of the input shaft 41 and the even-numbered intermediate shaft 43 using the even-numbered motor generator 24 when shifting from an odd-numbered gear to an even-numbered gear, and by performing synchronization control of the input shaft 41 and the odd-numbered intermediate shaft 42 using the odd-numbered motor generator 23 when shifting from an even-numbered gear to an odd-numbered gear, it is possible to eliminate the need to use a synchronizing device with a complex configuration such as a synchro mechanism, and it is possible to simplify the transmission 3 and reduce costs.

[0275] Furthermore, by reducing the engine torque during gear shifting, disturbances caused by rotational fluctuations of the engine 2 during gear shifting can be reduced, and the odd-numbered stage motor-generator 23 and the even-numbered stage motor-generator 24, which have higher torque responsiveness than the engine 2, can achieve synchronization between the input shaft 41 and the odd-numbered stage intermediate shaft 42 in a shorter time, and can also achieve synchronization between the input shaft 41 and the even-numbered stage intermediate shaft 43 in a shorter time.

[0276] In addition, the first-speed gear pair 45 and the third-speed gear pair 47 of this embodiment have a first-speed input gear 45A and a third-speed input gear 47A that are rotatable integrally with the odd-numbered intermediate shaft 42, and a first-speed output gear 45B and a third-speed output gear 47B that are rotatable relative to the output shaft 44 and mesh with the first-speed input gear 45A and the third-speed input gear 47A.

[0277] In addition, the second-speed gear pair 46 and the fourth-speed gear pair 48 of this embodiment have a second-speed input gear 46A and a fourth-speed input gear 48A that are rotatable integrally with the even-stage intermediate shaft 43, and a second-speed output gear 46B and a fourth-speed output gear 48B that are rotatable relative to the output shaft 44 and mesh with the second-speed input gear 46A and the fourth-speed input gear 48A, respectively.

[0278] In addition, the transmission 3 of this embodiment has a second dog clutch 53 that establishes first or third gear by connecting the first-speed output gear 45B or the third-speed output gear 47B to the output shaft 44 and rotating integrally with the output shaft 44.

[0279] In addition, the transmission 3 of this embodiment has a third dog clutch 54 that establishes second or fourth gear by connecting the second-speed output gear 46B or the fourth-speed output gear 48B to the output shaft 44 and rotating integrally with the output shaft 44.

[0280] As a result, after the first dog clutch 52 is switched to the odd-numbered gear position or the even-numbered gear position, by connecting any one of the first-speed output gear 45B to the fourth-speed output gear 48B to the output shaft 44 by the second dog clutch 53 or the third dog clutch 54, it is possible to achieve smooth gear changes by increasing the number of gears with a simple configuration. As a result, it is possible to prevent a deterioration in the drivability of the vehicle 1 and to perform gear changes without impairing the acceleration of the vehicle 1.

[0281] Furthermore, according to the transmission 3 of this embodiment, the odd-numbered-stage motor driven gear 50B is installed closest to the first dog clutch 52 in the axial direction of the odd-numbered-stage intermediate shaft 42, and the first-speed input gear 45A and the third-speed input gear 47A are installed on the opposite side of the odd-numbered-stage motor driven gear 50B from the first dog clutch 52.

[0282] In addition, the even-stage motor driven gear 51B is installed closest to the first dog clutch 52 in the axial direction of the even-stage intermediate shaft 43, and the second-speed input gear 46A and the fourth-speed input gear 48A are installed on the opposite side of the even-stage motor driven gear 51B from the first dog clutch 52.

[0283] The odd-numbered stage motor driven gear 50B, the first-speed input gear 45A, and the third-speed input gear 47A are arranged such that their diameters decrease in the order of odd-numbered stage motor driven gear 50B, third-speed input gear 47A, and first-speed input gear 45A as they move away from the first dog clutch 52 in the axial direction of the odd-numbered stage intermediate shaft 42.

[0284] The even-stage motor driven gear 51B, the second-speed input gear 46A, and the fourth-speed input gear 48A are arranged such that their diameters decrease in the order of the even-stage motor driven gear 51B, the fourth-speed input gear 48A, and the second-speed input gear 46A as they move away from the first dog clutch 52 in the axial direction of the even-stage intermediate shaft 43.

[0285] As a result, when the odd-numbered stage motor-generator 23 is installed so that its position overlaps with the positions of the first-speed input gear 45A and the third-speed input gear 47A in the axial direction of the odd-numbered stage intermediate shaft 42, the odd-numbered stage motor-generator 23 can be installed close to the odd-numbered stage intermediate shaft 42.

[0286] In addition, when the even-numbered motor-generator 24 is positioned so that it overlaps with the second-speed input gear 46A and the fourth-speed input gear 48A in the axial direction of the even-numbered intermediate shaft 43, the even-numbered motor-generator 24 can be positioned close to the even-numbered intermediate shaft 43. As a result, the transmission 3 can be made more compact.

[0287] Furthermore, in the transmission 3 of this embodiment, the gear pairs provided on the odd-numbered intermediate shaft 42 and the output shaft 44 are made up of a first-speed gear pair 45 and a third-speed gear pair 47, which are odd-numbered gears with different gear ratios, and the gear pairs provided on the even-numbered intermediate shaft 43 and the output shaft 44 are made up of a second-speed gear pair 46 and a fourth-speed gear pair 48, which are even-numbered gears with different gear ratios.

[0288] As a result, when shifting from odd-numbered gears to even-numbered gears, the engine torque is reduced to zero, the motor torque of the odd-numbered gear motor generator 23 is increased to compensate for the reduced engine torque, the rotation speed of the even-numbered gear intermediate shaft 43 that is shifting from odd-numbered gears to even-numbered gears is synchronized with the rotation speed of the input shaft 41, and after the rotation speed of the even-numbered gear intermediate shaft 43 and the rotation speed of the input shaft 41 are synchronized, the first dog clutch 52 is switched to the even-numbered gear position.

[0289] On the other hand, when shifting from an even gear to an odd gear, the engine torque is reduced to zero, the motor torque of the even gear motor generator 24 is increased to compensate for the reduced engine torque, the rotation speed of the odd gear intermediate shaft 42 that is shifting from an even gear to an odd gear is synchronized with the rotation speed of the input shaft 41, and after the rotation speed of the odd gear intermediate shaft 42 and the rotation speed of the input shaft 41 are synchronized, it becomes possible to implement control to switch the first dog clutch 52 to the odd gear position.

[0290] Therefore, a smooth gear change can be performed from either the odd-numbered gear or the even-numbered gear to the other, and deterioration of the drivability of the vehicle 1 can be suppressed.

[0291] Furthermore, in the transmission 3 of this embodiment, the switching member is made up of the first dog clutch 52, the second dog clutch 53, and the third dog clutch 54, so there is no need for a complex synchronizing device such as a synchro mechanism, and gear changes can be performed using the first dog clutch 52, the second dog clutch 53, and the third dog clutch 54, which have a simpler configuration than a synchro mechanism. This makes it possible to more effectively simplify the transmission 3 and more effectively reduce the manufacturing costs of the transmission 3.

[0292] In addition, the first dog clutch 52 can quickly and smoothly connect the rotation speed of the input shaft 41 and the rotation speed of the odd-numbered intermediate shaft 42 when the rotation speed of the input shaft 41 and the rotation speed of the odd-numbered intermediate shaft 42 are synchronized, for example.

[0293] In addition, the first dog clutch 52, the second dog clutch 53 and the third dog clutch 54 have a simple configuration, which improves durability and allows them to be used for a long period of time.

[0294] The vehicle 1 of this embodiment also has a coupling 33 made of a damper that constantly connects the engine 2 and the input shaft 41 and transmits engine torque to the input shaft 41 .

[0295] During gear shifting, the transmission 3 of this embodiment synchronizes the rotation speed of the input shaft 41 with the rotation speed of the odd-numbered stage intermediate shaft 42 using the odd-numbered stage motor-generator 23 and the even-numbered stage motor-generator 24, and also synchronizes the rotation speed of the input shaft 41 with the rotation speed of the even-numbered stage intermediate shaft 43. This allows the odd-numbered stage intermediate shaft 42 and the even-numbered stage intermediate shaft 43 to be connected to the input shaft 41 by the first dog clutch 52, thereby eliminating the need for a clutch device that connects and disconnects the engine 2 and the input shaft 41.

[0296] Therefore, instead of the clutch device, the coupling 33 made of a small and inexpensive damper can be used, which results in a reduction in the size and cost of the transmission 3.

[0297] Instead of the damper, the joint 33 may be provided with a clutch device that connects and disconnects the engine 2 and the input shaft 41 .

[0298] Here, disconnecting the engine 2 from the input shaft 41 by the clutch device means that the clutch device mechanically connects the crankshaft 2S of the engine 2 to the input shaft 41 when engine torque is transmitted from the engine 2 to the input shaft 41, and mechanically disconnects the crankshaft 2S of the engine 2 from the input shaft 41 when engine torque is not transmitted from the engine 2 to the input shaft 41.

[0299] In this way, by disengaging the clutch device during gear shifting to block the engine torque transmitted from the engine 2 to the input shaft 41, the rotation speed of the input shaft 41 and the rotation speed of the odd-numbered stage intermediate shaft 42 can be synchronized in a short time using the odd-numbered stage motor-generator 23 and the even-numbered stage motor-generator 24, and the rotation speed of the input shaft 41 and the rotation speed of the even-numbered stage intermediate shaft 43 can also be synchronized in a short time. This reduces the gear shift time.

[0300] In addition, in the transmission 3 of this embodiment, the odd-numbered intermediate shaft 42 and the output shaft 44 are connected by a first-speed gear pair 45 and a third-speed gear pair 47, and the even-numbered intermediate shaft 43 and the output shaft 44 are connected by a second-speed gear pair 46 and a fourth-speed gear pair 48, but the present invention is not limited to this.

[0301] For example, the odd-numbered stage intermediate shaft (first intermediate shaft) 42 and the output shaft 44 may be connected by a first-speed gear pair 45 and a second-speed gear pair 46 having different gear ratios, and the even-numbered stage intermediate shaft (second intermediate shaft) 43 and the output shaft 44 may be connected by a third-speed gear pair 47 and a fourth-speed gear pair 48 having different gear ratios from the first-speed gear pair 45 and the second-speed gear pair 46.

[0302] While an embodiment of the present invention has been disclosed, it will be apparent to one skilled in the art that modifications may be made thereto without departing from the scope of the present invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0303] 1... hybrid vehicle, 2... engine (internal combustion engine), 3... transmission, 23... odd-numbered-stage motor generator (first rotating electric machine), 24... even-numbered-stage motor generator (second rotating electric machine), 33... coupling (damper, clutch device), 41... input shaft, 42... odd-numbered-stage intermediate shaft (first intermediate shaft), 43... even-numbered-stage intermediate shaft (second intermediate shaft), 44... output shaft, 45... 1st-speed gear pair (first gear pair), 45A... 1st-speed input gear (first intermediate shaft side gear), 45B... 1st-speed output gear (first output shaft side gear), 46... 2nd-speed gear pair (second gear pair), 46A... 2nd-speed input gear (second intermediate shaft side gear), 46B... 2nd-speed output gear (second output shaft side gear), 47... 3rd-speed gear pair (first gear pair), 47A... 3rd-speed input gear (first intermediate shaft side gear), 47B...3rd-speed output gear (first output shaft side gear), 48...4th-speed gear pair (second gear pair), 48A...4th-speed input gear (second intermediate shaft side gear), 48B...4th-speed output gear (second output shaft side gear), 50A...odd-speed motor drive gear (first rotating electrical machine gear pair, first drive gear), 50B...odd-speed motor driven gear (first 1st rotating electric machine gear pair, first driven gear), 51A...even-numbered stage motor drive gear (second rotating electric machine gear pair, second drive gear), 51B...even-numbered stage motor driven gear (second rotating electric machine gear pair, second driven gear), 52...first dog clutch (first switching member), 53...second dog clutch (second switching member), 54...third dog clutch (third switching member)

Claims

1. A hybrid vehicle having a transmission that changes the speed of the driving force of an internal combustion engine and transmits it to drive wheels, The transmission is an input shaft to which the driving force of the internal combustion engine is transmitted; a first intermediate shaft provided coaxially with the input shaft and rotatable relative to the input shaft; a second intermediate shaft that is coaxial with the input shaft and faces the first intermediate shaft in the axial direction of the input shaft and is rotatable relative to the input shaft; an output shaft that is disposed parallel to the first intermediate shaft and the second intermediate shaft and transmits a driving force to the driving wheels; a first rotating electric machine connected to the first intermediate shaft so as to be able to transmit a driving force; a second rotating electric machine connected to the second intermediate shaft so as to be able to transmit a driving force; a first gear pair that connects the first intermediate shaft and the output shaft so as to be able to transmit a driving force and that constitutes a plurality of gear stages with different gear ratios; a second gear pair that connects the second intermediate shaft and the output shaft so as to be able to transmit a driving force and that constitutes a plurality of gear stages having gear ratios different from the gear ratio of the first gear pair; a first switching member that is switchable between a neutral position, a first position where the input shaft and the first intermediate shaft are connected, and a second position where the input shaft and the second intermediate shaft are connected, the first gear pair includes a plurality of first intermediate shaft side gears provided so as to be integrally rotatable with the first intermediate shaft, and a plurality of first output shaft side gears provided so as to be relatively rotatable with the output shaft and meshing with the plurality of first intermediate shaft side gears, respectively; the second gear pair includes a plurality of second intermediate shaft side gears provided so as to be integrally rotatable with the second intermediate shaft, and a plurality of second output shaft side gears provided so as to be relatively rotatable with the output shaft and meshing with the plurality of second intermediate shaft side gears, respectively; The transmission is a second switching member that connects any one of the plurality of first output shaft side gears to the output shaft and rotates integrally with the output shaft, thereby establishing a gear position corresponding to the first gear pair; and a third switching member that connects any one of the plurality of second output shaft side gears to the output shaft and rotates integrally with the output shaft, thereby establishing a gear position corresponding to the second gear pair; and a first rotating electric machine gear pair that connects the first rotating electric machine and the first intermediate shaft so as to be able to transmit a driving force; a second rotating electric machine gear pair that connects the second rotating electric machine and the second intermediate shaft so as to be able to transmit a driving force; the first switching member is disposed between the first intermediate shaft and the second intermediate shaft in the axial direction of the input shaft, the first rotating electric machine gear pair includes a first drive gear attached to the first rotating electric machine, and a first driven gear provided to be rotatable integrally with the first intermediate shaft and meshing with the first drive gear, the second rotating electric machine gear pair includes a second drive gear attached to the second rotating electric machine, and a second driven gear provided to be integrally rotatable with the second intermediate shaft and meshing with the second drive gear, the first driven gear is disposed closest to the first switching member in the axial direction of the first intermediate shaft, and the first intermediate shaft-side gear is disposed on the opposite side of the first driven gear to the first switching member, the second driven gear is disposed closest to the first switching member in the axial direction of the second intermediate shaft, and the second intermediate shaft side gear is disposed on the opposite side of the second driven gear to the first switching member, the first intermediate shaft gear and the first driven gear are disposed so that their diameters gradually decrease as they move away from the first switching member in the axial direction of the first intermediate shaft, a second intermediate shaft side gear and a second driven gear, the second intermediate shaft side gear and the second driven gear being disposed so that their diameters gradually decrease as they move away from the first switching member in the axial direction of the second intermediate shaft;

2. A hybrid vehicle as described in claim 1, characterized in that the first switching member, the second switching member and the third switching member are composed of dog clutches.

3. A hybrid vehicle as described in claim 1 or claim 2, characterized in that the first gear pair constitutes a plurality of odd-numbered gear stages with different gear ratios, and the second gear pair constitutes a plurality of even-numbered gear stages with different gear ratios.

4. A hybrid vehicle described in any one of claims 1 to 3, characterized in that it has a damper that constantly connects the internal combustion engine and the input shaft and transmits the driving force of the internal combustion engine to the input shaft.

5. A hybrid vehicle as described in any one of claims 1 to 4, characterized in that it has a clutch device that disconnects the internal combustion engine from the input shaft.

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