JP2015214248A - Vehicle drive device and vehicle drive method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle drive device and a vehicle drive method capable of reducing the shortage of a driving force during mode transition.SOLUTION: A vehicle drive device 1 comprises a control unit 70 switching travel modes over among a plurality of travel modes including a first travel mode of releasing a first fastening mechanism 12, fastening a second fastening mechanism 34, and causing a vehicle to travel by power output from a second motor 30, and a second travel mode of fastening the first fastening mechanism 12 and causing the vehicle to travel at least by power output from an internal combustion engine 10, the control unit 70 releasing the second fastening mechanism 34 and driving a first motor 20 by a counter electromotive force of the second motor 30 at a time of transition from the first travel mode to the second travel mode.

Description

  The present invention relates to a vehicle drive device and a vehicle drive method.

  2. Description of the Related Art Conventionally, an engine, a first shaft that is coaxially arranged with an output shaft of the engine, a first shaft that transmits power of the engine, a first shaft and a first transmission that are disposed in parallel with the first shaft. A second shaft composed of an inner peripheral shaft connected via a mechanism, a first outer peripheral shaft disposed around the inner peripheral shaft so as to be rotatable relative to the inner peripheral shaft, and an inner peripheral shaft; The first electric motor, the second electric motor arranged on the same axis as the first electric motor, connected to the first outer peripheral shaft, arranged parallel to the second axis, and the first electric motor A third shaft connected to the outer peripheral shaft of the first shaft through the second transmission mechanism, a differential device connected to the third shaft, and the first shaft and the third shaft provided on the first shaft There is known a hybrid vehicle drive device comprising a connection / disconnection means for connecting or releasing a shaft via a third transmission mechanism ( In example, see Patent Document 1).

International Publication No. 2009/128288

  In the hybrid vehicle as described above, when attempting to reduce the size of the electric motor that outputs power to the driving wheels, the driving force and the upper limit rotational speed may be insufficient. As a result, when switching from motor traveling to engine traveling, a driving force shortage (insufficient assisting force by the electric motor) may occur.

  The present invention has been made in view of such circumstances, and one of its objects is to provide a vehicle driving device and a vehicle driving method capable of reducing deficiencies in driving force during mode transition. To do.

  The invention according to claim 1 is an internal combustion engine (10), a first electric motor (20) connected to an output shaft of the internal combustion engine, a second electric motor (30) connected to drive wheels (46), A first fastening mechanism (12) for bringing the internal combustion engine and the driving wheel into a fastening state or a releasing state, and a second fastening mechanism for bringing the second motor and the driving wheel into a fastening state or a release state. (34), a first travel mode in which the first fastening mechanism is in a released state and the second fastening mechanism is in a fastened state and travels by the output of the second electric motor, and the first fastening mechanism is in a fastened state. A control unit (70) that switches between a plurality of travel modes including at least a second travel mode that travels by the output of the internal combustion engine, wherein the control unit is configured to switch the second travel mode from the first travel mode to the second travel mode. When shifting to driving mode The second and the fastening mechanism in the released state, the driving the first electric motor by back electromotive force that the second electric motor has a vehicle drive device (1).

  According to a second aspect of the present invention, in the first aspect of the present invention, after the control unit shifts from the first travel mode to the second travel mode, the output of the internal combustion engine reaches a target value. Sometimes, the output of the first electric motor is stopped.

  According to a third aspect of the present invention, the internal combustion engine (10), the first electric motor (20), the second electric motor (30), and the internal combustion engine and the drive wheel (46) are in a fastened state or a released state. The first fastening mechanism (12), the second fastening mechanism (34A) for fastening or releasing the first motor and the internal combustion engine, and the first fastening mechanism for releasing the first fastening mechanism (34A). (2) A control unit that switches between a plurality of travel modes including a first travel mode that travels by the output of the electric motor and a second travel mode that travels by at least the output of the internal combustion engine with the first fastening mechanism engaged. 70), and when the control unit shifts from the first travel mode to the second travel mode, the control unit sets the second fastening mechanism in a released state, and uses the back electromotive force of the first electric motor. The second electric motor Thereby moving a vehicle drive unit (2).

  According to a fourth aspect of the present invention, in the third aspect of the present invention, after the control unit shifts from the first travel mode to the second travel mode, the output of the internal combustion engine reaches a target value. Sometimes, the output of the second electric motor is stopped.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the first motor and the second motor are motors having substantially the same size and / or the same specifications. Is.

  According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects of the present invention, the control unit is configured such that the vehicle speed is an upper limit rotation of the second electric motor at which the second electric motor can output a driving force. When the vehicle speed exceeds the upper limit vehicle speed corresponding to the number, control is performed so as to shift from the first travel mode to the second travel mode.

  The invention according to claim 7 is an internal combustion engine (10), a first electric motor (20) connected to an output shaft of the internal combustion engine, a second electric motor (30) connected to drive wheels (46), A first fastening mechanism (12) for bringing the internal combustion engine and the driving wheel into a fastening state or a releasing state, and a second fastening mechanism for bringing the second motor and the driving wheel into a fastening state or a release state. (34), the vehicle control computer (70) includes a first travel that causes the first fastening mechanism to be in a released state and the second fastening mechanism to be in a fastened state to travel according to the output of the second electric motor. A plurality of travel modes including a mode and a second travel mode in which the first fastening mechanism is engaged and travels at least by the output of the internal combustion engine, and the second travel mode is switched from the first travel mode. When moving to In the second and the fastening mechanism in the released state, to drive said first motor by back electromotive force that the second electric motor has a vehicle driving method.

  The invention according to claim 8 includes an internal combustion engine (10), a first electric motor (20) coupled to an output shaft of the internal combustion engine, a second electric motor (30), the internal combustion engine, and the drive wheels. A vehicle comprising: a first fastening mechanism (12) that puts a gap between the first motor and the internal combustion engine; and a second fastening mechanism (34A) that puts the gap between the first electric motor and the internal combustion engine. A control computer has a first traveling mode in which the first fastening mechanism is in a released state and travels by the output of the second electric motor, and a first traveling mode in which the first fastening mechanism is in a fastening state and travels by at least the output of the internal combustion engine. When the plurality of travel modes including the second travel mode are switched and the first travel mode is shifted to the second travel mode, the second fastening mechanism is released, and the reverse of the first electric motor is provided. Electromotive force Therefore to drive the second electric motor, a vehicle driving method.

  According to invention of Claim 1, 7, the 2nd fastening mechanism which makes a fastening state or a release state between a 2nd electric motor and a driving wheel is provided, and it transfers to a 2nd running mode from a 1st running mode. Sometimes, the first electric motor is driven by the counter electromotive force generated in the second electric motor by bringing the second fastening mechanism into the released state, so that it is possible to reduce the driving force shortage at the time of mode transition.

  According to the second aspect of the present invention, in order to stop the output of the first electric motor when the output of the internal combustion engine reaches the target value after shifting from the first travel mode to the second travel mode, The fluctuation of the driving force can be made smoother.

  According to the third and eighth aspects of the present invention, the second fastening mechanism for bringing the first electric motor and the internal combustion engine into a fastening state or a releasing state is provided, and the first traveling mode is changed to the second traveling mode. When shifting, the second motor is driven by the back electromotive force generated in the first motor by putting the second fastening mechanism in the released state, so that it is possible to reduce driving power shortage at the time of mode transition.

  According to the invention of claim 4, in order to stop the output of the second electric motor when the output of the internal combustion engine reaches a target value after shifting from the first travel mode to the second travel mode, The fluctuation of the driving force can be made smoother.

According to the invention described in claim 5, since the first motor and the second motor are motors of substantially the same size, it is possible to prevent the occurrence of dead space and to reduce the size of the entire apparatus.
Further, the first motor and the second motor can have the same specifications. Thereby, for example, the cost of the electric motor can be reduced and the manufacturability is improved. Furthermore, since the vibration region is the same, resonance and the like can be easily prevented, and NV (noise / vibration) performance can be improved.

It is a figure which shows typically an example of a structure of the vehicle drive device 1 which concerns on 1st Embodiment. 2 is a cross-sectional view showing an example of a connection structure in the vehicle drive device 1. FIG. It is a figure which shows the flow of the driving force in series operation mode. It is a figure which shows the flow of the driving force in EV driving | running | working mode. It is a figure which shows the flow of the driving force in direct connection stage assist mode. It is a figure which shows the flow of the driving force in direct connection stage cruise mode. It is the figure which compared the operating point in the case where the reduction ratio of the motor drive gear 36 is small, and when it is large. It is a figure which shows a mode that driving force shortage arises. It is a flowchart which shows an example of the flow of the rough process performed by hybrid ECU70 which concerns on 1st Embodiment. It is a figure which shows typically an example of a structure of the vehicle drive device 2 which concerns on 2nd Embodiment. It is a flowchart which shows an example of the flow of a rough process performed by hybrid ECU70 which concerns on 2nd Embodiment.

  Hereinafter, embodiments of a vehicle drive device and a vehicle drive method of the present invention will be described with reference to the drawings.

<First Embodiment>
FIG. 1 is a diagram schematically illustrating an example of a configuration of a vehicle drive device 1 according to the first embodiment. The vehicle drive device 1 includes, for example, an engine (internal combustion engine) 10, a first clutch (first fastening mechanism) 12, a generator (first electric motor) 20, a motor (second electric motor) 30, and a second clutch ( A second fastening mechanism) 34 and a hybrid ECU (Electronic Control Unit) 70. Generator 20 and motor 30 are electrically connected to battery BT. The battery BT is a secondary battery that stores electric power generated by the generator 20 and the motor 30 and supplies electric power for powering the generator 20 and the motor 30 and electric power used by various electric devices in the vehicle.

  The engine 10 is an internal combustion engine that outputs power by burning hydrocarbon fuel such as gasoline. The engine shaft 11 connected to the crankshaft of the engine 10 is connected to a generator shaft 23 that is an output shaft of the generator 20 via a generator drive gear 13. The engine shaft 11 is connected to the idler shaft 40 via the first clutch 12 and the engine driving force transmission gear 14. The idler shaft 40 is connected to the drive wheels 46 via a final gear 42 and a differential gear 44.

  The motor shaft 33 which is an output shaft of the motor 30 is a hollow shaft whose rotation center coincides with, for example, the generator shaft 23, includes the generator shaft 23, and is rotatably held with the generator shaft 23. With such a configuration, the rotation center of the generator 20 and the motor 30 can be aligned. The motor shaft 33 is connected to the idler shaft 40 via the second clutch 34 and the motor drive gear 36.

  FIG. 2 is a cross-sectional view showing an example of a connection structure in the vehicle drive device 1. The generator 20 and the motor 30 of the vehicle drive device 1 are housed in a case 50, and the case 50 is fixed to a damper housing 51. In the case 50, the engine shaft 11, the generator shaft 23, the motor shaft 33, and the idler shaft 40 are arranged in parallel to each other.

  The engine shaft 11 is supported on the damper housing 51 on the engine 10 side by a bearing, and supported on the case 50 by a bearing 52 on the side opposite to the engine 10. The driving force of the crankshaft is transmitted to the engine shaft 11 via the drive plate 11a and the damper 53. An output gear 13a that constitutes the generator drive gear 13 is provided at the axial center of the engine shaft 11, and a first clutch 12 is provided on the opposite side of the output gear 13a from the engine 10.

  The first clutch 12 is, for example, a multi-plate clutch, and includes a plurality of disc-shaped clutch disks and clutch plates, and a clutch piston that urges the clutch disks and the clutch plates. The outer peripheral portion is held by a cylindrical outer diameter hub and is movable in the axial direction. The plurality of clutch plates have an inner peripheral portion held by a cylindrical inner diameter hub and are movable in the axial direction. The clutch disks and the clutch plates are arranged in parallel with each other and alternately stacked with an interval in the axial direction.

  The first clutch 12 is configured such that the clutch disk and the clutch plate can be brought into contact with and separated from each other by controlling the hydraulic pressure in the working chamber. When the pressure in the working chamber decreases to a predetermined value, the clutch piston moves to the engine 10 side, the adjacent clutch disc and the clutch plate are separated, and the first clutch 12 is released. At this time, the driving force of the engine shaft 11 is not transmitted to the engine driving force transmission gear 14 via the first clutch 12. On the other hand, when the pressure in the working chamber is increased and the pressure in the working chamber becomes higher than a predetermined value, the clutch piston moves to the side opposite to the engine 10. Along with this, the clutch piston urges the clutch disk and the clutch plate to move to the opposite side of the engine and is clamped between the stopper on the opposite side. As a result, the adjacent clutch disk and the clutch plate are frictionally engaged, and the first clutch 12 is brought into the engaged state. At this time, the driving force of the engine shaft 11 is transmitted to the driving force transmission gear 14 including the output gear 14 a and the input gear 14 b and is transmitted to the idler shaft 40. The driving force of engine shaft 11 is simultaneously transmitted to generator shaft 23 via generator driving gear 13 (output gear 13a and input gear 13b).

  The generator shaft 23 is formed with an input gear 13 b that constitutes a part of the generator drive gear 13. The generator shaft 23 is attached to the case 50 so that the rotor 21 of the generator 20 can rotate integrally therewith, and is supported by the case 50 by a bearing 54 at the end on the engine 10 side and by a bearing 55 at the end opposite to the engine 10. The generator 20 includes a rotor 21 whose inner peripheral side end is fixed to the generator shaft 23, and a stator 22 that is fixed to the case 50 and disposed opposite to the rotor 21. The driving force of the engine shaft 11 is transmitted to the generator shaft 23 via the generator driving gear 13. Therefore, the generator 20 can generate electric power using the driving force of the engine 10.

  A rotor 31 of a motor 30 is attached to the motor shaft 33 so as to be integrally rotatable, and an output gear 14a constituting a motor driving force transmission gear is provided at an end portion on the engine 10 side. The motor shaft 33 is supported on the case 50 by a bearing 56 disposed between the motor 30 and the output gear 14 a and a bearing 57 at the end opposite to the engine 10. The motor 30 includes a rotor 31 whose inner peripheral side end is fixed to the motor shaft 33, and a stator 32 that is fixed to the case 50 and disposed opposite to the rotor 31.

  A second clutch 34 is provided in the middle of the motor shaft 33. The second clutch 34 is a dog clutch, for example. A thrust bearing and a needle bearing are provided around the second clutch so as to be able to absorb an impact at the time of engagement and release.

  Further, the generator 20 and the motor 30 may have the same size in width w (see FIG. 2) and radius r.

  The idler shaft 40 includes, in order from the engine 10 side, an output gear 42 a that constitutes the final gear 42, and an input gear 14 b that meshes with the output gear 14 a of the motor shaft 33 and the engine shaft 11 to constitute the driving force transmission gear 14. Yes. With such a configuration, both the driving force input from the engine 10 and the driving force input from the motor 30 are transmitted to the final gear 42 via the driving force transmission gear 14. As a result, the number of gears is reduced, and the device Can be reduced in size. The engine 10 side end of the idler shaft 40 is supported by the damper housing 51 by a bearing 58, and the side end opposite to the engine 10 is supported by the case 50 by a bearing 59.

  When the motor 30 is rotated by the electric power supplied from the generator 20 or the battery BT, the motor shaft 33 rotates, and the output gear 14a of the motor shaft 33 and the input gear 14b of the idler shaft 40 constituting the driving force transmission gear 14 are rotated. The driving force of the motor 30 is transmitted to the idler shaft 40 by meshing.

  Further, the output gear 14a of the engine shaft 11 constituting the driving force transmission gear 14 and the input gear 14b of the idler shaft 40 mesh with each other, whereby the driving force of the engine 10 is transmitted to the idler shaft 40 when the clutch 12 is engaged. .

  In the differential gear 44, the differential shaft 45 is arranged in parallel with the idler shaft 40, the end portion on the engine 10 side is supported by the damper housing 51 by the bearing 60, and the end portion on the opposite side to the engine 10 is supported by the case 50 by the bearing 61. The The differential gear 44 includes an input gear 42b that constitutes a final gear 42. The differential gear 44 meshes with the output gear 42a of the idler shaft 40, so that the driving force of the motor 30 and the driving force of the engine 10 input to the idler shaft 40 can be changed to the differential shaft 45. And the driving wheel 46 is rotated via the differential shaft 45.

  With this configuration, the vehicle drive device 1 according to the first embodiment places the first clutch 12 in the released state, operates the engine 10, and the generator 20 generates power using the driving force output to the engine shaft 11, The series operation mode in which the motor 30 outputs the driving force for traveling using the power generated by the generator 20 is executed. FIG. 3 is a diagram showing the flow of driving force in the series operation mode. In the figure, arrows indicate the flow of driving force.

  Further, when the battery BT has a sufficient charging rate (SOC; State Of Charge), the vehicle drive device 1 according to the first embodiment disengages the first clutch 12, stops the engine 10 and the generator 20, and stops the motor The EV traveling mode in which 30 outputs the driving force for traveling using the electric power from the battery BT is executable. FIG. 4 is a diagram illustrating a flow of driving force in the EV traveling mode. In the figure, arrows indicate the flow of driving force.

  In addition, the vehicle drive device 1 according to the first embodiment can execute the direct connection stage assist mode in which the first clutch 12 is engaged and the driving force for traveling is output from both the engine 10 and the generator 20. Yes. In this case, the generator 20 outputs a driving force for rotating the generator shaft 23 in the same direction as the engine 10 rotates the engine shaft 11. At this time, since the drag resistance of the motor 30 does not occur by bringing the second clutch 34 into the released state, the energy efficiency can be improved as compared with the case where the second clutch 34 is not provided. FIG. 5 is a diagram showing the flow of driving force in the direct coupling stage assist mode. In the figure, arrows indicate the flow of driving force.

  Further, in the vehicle drive device 1 according to the first embodiment, the first clutch 12 is engaged, the driving force for traveling is output from the engine 10, and the generator 20 generates power using the driving force output from the engine 10. The direct coupled cruise mode can be executed. In this case, the generator 20 outputs a driving force for rotating the generator shaft 23 in the direction opposite to the direction in which the engine 10 rotates the engine shaft 11. Also in this case, since the drag resistance of the motor 30 does not occur by putting the second clutch 34 in the released state, the energy efficiency can be improved as compared with the case where the second clutch 34 is not provided. . FIG. 6 is a diagram showing the flow of driving force in the direct coupled cruise mode. In the figure, arrows indicate the flow of driving force.

  As described above, it is preferable that the generator 20 and the motor 30 have the same size and the same specifications. In general, a motor that outputs a driving force for traveling to a differential gear is often larger than a generator that generates electric power using the driving force of the engine. Therefore, when the generator 20 and the motor 30 have the same size and the same specification, the size of the motor 30 is reduced. However, if nothing is done, the maximum driving force that can be output from the motor 30 decreases, and as a result, the traveling performance of the vehicle on which the vehicle driving device 1 is mounted decreases.

  FIG. 7 is a diagram showing an efficiency map of the motor 30. FIG. 7A is an efficiency map of the motor 30 when the generator 20 and the motor 30 have different sizes and specifications, that is, the above-described general configuration. In the case of this configuration, the target driving force can be output by the output of the motor 30, so the reduction ratio until the driving force output from the motor 30 is output to the driving wheels via the drive gear 14 is set to be small. The That is, the motor 30 can rotate at a high speed so that a driving force sufficient to output the high vehicle speed V3 can be output. Thereby, the running performance of the vehicle can be output up to the possible output of the motor 30. However, in the case of this configuration, the size of the motor 30 is large and the output is large. For example, in the case of daily use, an area outside the high efficiency point of the motor 30 (the operation point in FIG. 7A). Will work. Therefore, the motor 30 is inefficiently operated.

  On the other hand, FIG. 7B is an efficiency map of the motor 30 when the generator 20 and the motor 30 have the same size and the same specifications. In the case of this configuration, the target driving force cannot be output with the output of the motor 30. That is, the motor 30 is set to a rotation speed at which a driving force that can only be output up to the vehicle speed V1 can be output. Therefore, the reduction ratio until the driving force output from the motor 30 is output to the drive wheels via the drive gear 14 is set large. As a result, the running performance of the vehicle can be output to a range that exceeds the possible output of the motor 30. Further, in the case of the configuration, since the size of the motor 30 is small and the output is small, for example, in the case of daily use, in the region including the high efficiency point of the motor 30 (the operation point in FIG. 7B). Will work. Therefore, the motor 30 is operated efficiently.

  Here, when the vehicle travels at a speed higher than the vehicle speed V1 shown in FIG. 7B, the motor 30 can no longer output the driving force, so the vehicle drive device 1 is in the direct connection stage assist mode or the direct connection stage. It is controlled to run in the cruise mode. At this time, if the driving force output by the engine 10 is sufficiently increased, the operation mode is changed to the series operation mode, the EV travel mode (first travel mode), the direct connection stage assist mode or the direct connection stage cruise mode (second travel mode). There is no shortage of driving force when shifting. However, when the driving force output from the engine 10 is not sufficiently increased, the driving force is insufficient. FIG. 8 is a diagram illustrating a state in which the driving force is insufficient.

  Therefore, the vehicle drive device 1 according to the first embodiment releases the second clutch 34 when the hybrid ECU 70 controls to shift from the first travel mode to the second travel mode by exceeding the vehicle speed V1. The back electromotive force generated in the motor 30 by setting the state, more specifically, the back electromotive force generated by driving the motor 30 in the EV traveling mode, and the inertia generated by opening the second clutch 34 The generator 20 is driven by the back electromotive force generated by. As a result, deficiency in driving force at the time of mode transition can be reduced. By using the counter electromotive force generated in the motor 30 by disengaging the second clutch 34, it is possible to reduce driving power shortage even when the charging rate of the battery BT is low.

  Hereinafter, the control of the hybrid ECU 70 will be described. The hybrid ECU 70 has, for example, a configuration in which a processor such as a CPU (Central Processing Unit), various memories, a communication interface, and the like are connected via a bus. The hybrid ECU 70 is connected to sensors and control devices such as an accelerator opening sensor 71, a vehicle speed sensor 72, a brake pedal sensor 73, and a battery ECU 74, and inputs an accelerator opening, a vehicle speed, a brake pedal stroke, a charging rate of the battery BT, and the like. Is done.

  FIG. 9 is a flowchart showing an example of a rough processing flow executed by the hybrid ECU 70. First, the hybrid ECU 70 determines whether or not the current travel mode is the series operation mode or the EV travel mode (step S100). When the current travel mode is the series operation mode or the EV travel mode, the hybrid ECU 70 determines whether or not the vehicle speed V has increased to be equal to or higher than the vehicle speed V1 (step S102). When the vehicle speed V increases and does not exceed the vehicle speed V1, that is, when the driving force of the motor 30 does not exceed the upper limit number of rotations that can be output, one routine of this flowchart ends.

  In the series operation mode or the EV travel mode, when the vehicle speed V increases and becomes equal to or higher than the vehicle speed V1, that is, when the driving force of the motor 30 becomes equal to or higher than the upper limit number of rotations that can be output, the hybrid ECU 70 The driving force output to the wheel is compared with the driving force that can be output from the engine 10 to determine whether or not the driving force is insufficient (step S104).

  When it is determined that the driving force is insufficient, the hybrid ECU 70 outputs a power running instruction to a driving circuit (not shown) of the generator 20 (step S106), and the first clutch 12 is engaged and the second clutch 34 is released (step S106). Step S108). Thereby, as described above, the generator 20 can output the assist driving force by the counter electromotive force generated in the motor 30 by bringing the second clutch 34 into the released state. The hybrid ECU 70 continues this state until the driving force output from the engine 10 reaches the target value (step S114).

  On the other hand, when it is determined that the driving force is not insufficient, the hybrid ECU 70 outputs a regeneration instruction to a driving circuit (not shown) of the generator 20 (step S110), engages the first clutch 12, and activates the second clutch 34. Release (step S112). In this case, the driving force necessary for traveling is covered by the engine 10, and the generator 20 generates power using the surplus driving force.

  Thereafter, the hybrid ECU 70 determines whether or not the assist driving force by the generator 20 is necessary (step S116). This determination is comprehensively performed in consideration of the accelerator opening AC input from the accelerator opening sensor 71, the vehicle speed V input from the vehicle speed sensor 72, the charging rate SOC of the battery BT input from the battery ECU 74, and the like. Is called. When the hybrid ECU 70 determines that the assist driving force by the generator 20 is necessary, the hybrid ECU 70 controls the generator 20 to travel in the direct connection assist mode (step S118). When it determines that the assist driving force by the generator 20 is not required, the hybrid ECU 70 The generator 20 is controlled to run in the mode (step S120).

  When it is determined in step S100 that the vehicle is not in the series operation mode or the EV travel mode, that is, the direct connection assist mode or the direct connection cruise mode, the hybrid ECU 70 determines whether or not the vehicle speed V has decreased to the vehicle speed V2 or less (step). S122). The vehicle speed V2 is set to a value slightly lower than the vehicle speed V1 in consideration of hunting. When the vehicle speed V decreases and becomes equal to or lower than the vehicle speed V2, the hybrid ECU 70 controls the clutch 12 and the like so as to shift to the series operation mode or the EV travel mode (step S124).

  According to the vehicle drive device 1 according to the first embodiment described above, the reverse generated in the motor 30 by bringing the second clutch 34 into the released state when shifting from the first travel mode to the second travel mode. Since the generator 20 is driven by the electromotive force, deficiency in driving force at the time of mode transition can be reduced.

  Further, according to the vehicle drive device 1 according to the first embodiment, after the generator 20 is driven by the counter electromotive force generated in the motor 30 by bringing the second clutch 34 into the released state, the driving force output from the engine 10 is increased. Since waiting for the target value to be reached and then shifting to the direct-coupled cruise mode as necessary, fluctuations in driving force can be made smoother.

  In addition, according to the vehicle drive device 1 according to the first embodiment, the generator 20 and the motor 30 are approximately the same size and substantially the same specification, thereby preventing dead space from occurring and reducing the overall size of the device. can do.

Second Embodiment
Hereinafter, the vehicle drive device 2 according to the second embodiment will be described. Here, description of matters common to the first embodiment is omitted, and differences will be mainly described.

  FIG. 10 is a diagram schematically illustrating an example of the configuration of the vehicle drive device 2 according to the second embodiment. Compared with FIG. 1, the vehicle drive device 2 according to the second embodiment is different in that a second clutch 34 </ b> A is provided instead of the second clutch 34. The second clutch 34 </ b> A is provided at an arbitrary position between the engine 10 and the generator 20.

  The hybrid ECU 70 according to the second embodiment drives the motor 30 by the counter electromotive force generated in the generator 20 by disengaging the second clutch 34A when shifting from the first travel mode to the second travel mode. To do. As a result, as in the first embodiment, it is possible to reduce deficiencies in driving force during mode transition.

  FIG. 11 is a flowchart illustrating an example of a rough process executed by the hybrid ECU 70 according to the second embodiment. First, the hybrid ECU 70 determines whether or not the current travel mode is the series operation mode or the EV travel mode (step S100). When the current travel mode is the series operation mode or the EV travel mode, the hybrid ECU 70 determines whether or not the vehicle speed V has increased to be equal to or higher than the vehicle speed V1 (step S102). When the vehicle speed V increases and does not exceed the vehicle speed V1, that is, when the driving force of the motor 30 does not exceed the upper limit number of rotations that can be output, one routine of this flowchart ends.

  In the series operation mode or the EV travel mode, when the vehicle speed V increases and becomes equal to or higher than the vehicle speed V1, that is, when the driving force of the motor 30 becomes equal to or higher than the upper limit number of rotations that can be output, the hybrid ECU 70 The driving force output to the wheel is compared with the driving force that can be output from the engine 10 to determine whether or not the driving force is insufficient (step S104).

  When it is determined that the driving force is insufficient, the hybrid ECU 70 continues to drive the motor 30 (step S107). Further, the hybrid ECU 70 engages the first clutch 12 and releases the second clutch 34A (step S108). Thereby, the motor 30 can output the assist driving force by the counter electromotive force generated in the generator 20. The hybrid ECU 70 maintains this state until the driving force output from the engine 10 reaches the target value (step S114), and then stops the motor 30. In this case, zero driving force control may be performed on the motor 30.

  On the other hand, when it is determined that the driving force is not insufficient, the hybrid ECU 70 instructs a driving circuit (not shown) of the motor 30 to gradually stop the motor 30 (step S111), and the first clutch 12 is engaged. (Step S113). In this case, the state of the second clutch 34A may be arbitrarily determined according to various conditions.

  Thereafter, the hybrid ECU 70 determines whether or not an assist driving force by the motor 30 is necessary (step S116). This determination is comprehensively performed in consideration of the accelerator opening AC input from the accelerator opening sensor 71, the vehicle speed V input from the vehicle speed sensor 72, the charging rate SOC of the battery BT input from the battery ECU 74, and the like. Is called. When the hybrid ECU 70 determines that the assist driving force by the motor 30 is necessary, the hybrid ECU 70 controls the motor 30 to travel in the direct connection assist mode (step S118). When the hybrid ECU 70 determines that the assist driving force by the motor 30 is unnecessary, the direct cruise The motor 30 is controlled to travel in the mode (step S120).

  When it is determined in step S100 that the vehicle is not in the series operation mode or the EV travel mode, that is, the direct connection assist mode or the direct connection cruise mode, the hybrid ECU 70 determines whether or not the vehicle speed V has decreased to the vehicle speed V2 or less (step). S122). The vehicle speed V2 is set to a value slightly lower than the vehicle speed V1 in consideration of hunting. When the vehicle speed V decreases and becomes equal to or lower than the vehicle speed V2, the hybrid ECU 70 controls the clutch 12 and the like so as to shift to the series operation mode or the EV travel mode (step S124).

  According to the vehicle drive device 2 according to the second embodiment described above, the reverse generated in the generator 20 by bringing the second clutch 34A into the disengaged state when shifting from the first travel mode to the second travel mode. Since the motor 30 is driven by the electromotive force, deficiency in driving force at the time of mode transition can be reduced.

  Further, according to the vehicle drive device 2 according to the second embodiment, after the motor 30 is driven by the counter electromotive force generated in the generator 20 by disengaging the second clutch 34A, the driving force output by the engine 10 is increased. Since waiting for the target value to be reached and then shifting to the direct-coupled cruise mode as necessary, fluctuations in driving force can be made smoother.

  In addition, according to the vehicle drive device 2 according to the second embodiment, the generator 20 and the motor 30 are approximately the same size and substantially the same specification, thereby preventing the occurrence of dead space and reducing the overall size of the device. can do.

  As mentioned above, although the form for implementing this invention was demonstrated using embodiment, this invention is not limited to such embodiment at all, In the range which does not deviate from the summary of this invention, various deformation | transformation and substitution Can be added.

DESCRIPTION OF SYMBOLS 1, 2 Vehicle drive device 10 Engine 12 1st clutch (1st fastening mechanism)
20 Generator (first motor)
30 motor (second motor)
34 Second clutch (second engagement mechanism)
70 Hybrid ECU (control unit)

Claims (8)

An internal combustion engine;
A first electric motor coupled to the output shaft of the internal combustion engine;
A second electric motor coupled to the drive wheel;
A first fastening mechanism for bringing the internal combustion engine and the drive wheel into a fastening state or a releasing state;
A second fastening mechanism for bringing the second motor and the drive wheel into a fastening state or a releasing state;
A first travel mode in which the first fastening mechanism is in a released state and the second fastening mechanism is in a fastened state to travel by the output of the second electric motor; and the first fastening mechanism is in a fastened state and at least the internal combustion engine A controller that switches between a plurality of travel modes including a second travel mode that travels by the output of the engine,
When the control unit shifts from the first traveling mode to the second traveling mode, the control unit releases the second fastening mechanism and drives the first motor by a counter electromotive force of the second motor. Let
Vehicle drive device. The control unit stops the output of the first electric motor when the output of the internal combustion engine reaches a target value after transitioning from the first travel mode to the second travel mode.
The vehicle drive device according to claim 1. An internal combustion engine;
A first electric motor;
A second electric motor;
A first fastening mechanism for bringing the internal combustion engine and the drive wheel into a fastening state or a releasing state;
A second fastening mechanism for bringing the first electric motor and the internal combustion engine into a fastening state or a releasing state;
A first travel mode in which the first fastening mechanism is in a released state and travels by the output of the second electric motor, and a second travel mode in which the first fastening mechanism is in a fastened state and travels by at least the output of the internal combustion engine. And a controller that switches between a plurality of driving modes including
When the control unit shifts from the first travel mode to the second travel mode, the control unit releases the second fastening mechanism and drives the second motor by a counter electromotive force of the first motor. Let
Vehicle drive device. The control unit stops the output of the second electric motor when the output of the internal combustion engine reaches a target value after transitioning from the first travel mode to the second travel mode.
The vehicle drive device according to claim 3. The first motor and the second motor are motors having substantially the same size and / or substantially the same specifications.
The vehicle drive device according to any one of claims 1 to 4. When the vehicle speed becomes equal to or higher than the upper limit vehicle speed corresponding to the upper limit rotational speed of the second electric motor at which the second electric motor can output a driving force, the control unit starts from the first travel mode and performs the second operation. Control to shift to driving mode,
The vehicle drive device according to any one of claims 1 to 5. An internal combustion engine;
A first electric motor coupled to the output shaft of the internal combustion engine;
A second electric motor coupled to the drive wheel;
A first fastening mechanism for bringing the internal combustion engine and the drive wheel into a fastening state or a releasing state;
A second fastening mechanism for bringing the second motor and the drive wheel into a fastening state or a releasing state;
A vehicle control computer comprising:
A first travel mode in which the first fastening mechanism is in a released state and the second fastening mechanism is in a fastened state to travel by the output of the second electric motor; and the first fastening mechanism is in a fastened state and at least the internal combustion engine Switching between a plurality of travel modes including a second travel mode that travels by the output of the engine,
When shifting from the first travel mode to the second travel mode, the second fastening mechanism is released, and the first motor is driven by the counter electromotive force of the second motor;
Vehicle driving method. An internal combustion engine;
A first electric motor;
A second electric motor;
A first fastening mechanism for bringing the internal combustion engine and the drive wheel into a fastening state or a releasing state;
A second fastening mechanism for bringing the first electric motor and the internal combustion engine into a fastening state or a releasing state;
A vehicle control computer comprising:
A first travel mode in which the first fastening mechanism is in a released state and travels by the output of the second electric motor, and a second travel mode in which the first fastening mechanism is in a fastened state and travels by at least the output of the internal combustion engine. Switch between multiple driving modes including
When shifting from the first travel mode to the second travel mode, the second fastening mechanism is brought into a released state, and the second motor is driven by a counter electromotive force of the first motor;
Vehicle driving method.

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