JP2010076625A - Hybrid car - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control technology of a hybrid car for determining a start stage of the optimal deceleration rate in consideration whether or not responsiveness is necessary in response to a request for the start of an internal combustion engine in cranking during EV traveling. <P>SOLUTION: When a request is made to start an internal combustion engine 5 during EV traveling, an ECU 100 of a hybrid car 1 determines a start stage of transmission for engaging an engine output shaft with a drive wheel in cranking for starting an internal combustion engine 5, in accordance with whether or not responsiveness is necessary in response to a request for the start of the internal combustion engine 5. When a request is made to start the internal combustion engine 5 in accordance with an increase of required drive force, the ECU 100 of the hybrid car 1 decides that responsiveness is necessary for the start of the combustion engine 5. When a request is made to start the internal combustion engine 5 according to a reduction in state of charge (SOC) of a secondary battery 120, the ECU decides that responsiveness is not necessary. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control technique for a hybrid vehicle including a dual clutch transmission.

  In recent years, in a vehicle transmission, mechanical power received by a first input shaft is shifted by any one of a plurality of shift stages (for example, odd gear stages) and transmitted to drive wheels. A first transmission mechanism capable of transmitting the mechanical power received by the second input shaft and the second input shaft by any one of a plurality of shift stages (for example, even gear stages) and transmitting it to the drive wheels. A second transmission mechanism, a first clutch capable of engaging the engine output shaft and the first input shaft, and a second clutch capable of engaging the engine output shaft and the second input shaft. A so-called dual clutch transmission is known (see, for example, Patent Document 1). In the dual clutch transmission, the first clutch and the second clutch are alternately engaged to change the gear stage for shifting the mechanical power from the internal combustion engine between the first transmission mechanism and the second transmission mechanism. When switching between, the transmission of power from the engine output shaft to the drive wheels is prevented from being interrupted.

  Patent Document 1 discloses a hybrid vehicle that includes a dual clutch type (twin clutch type) transmission and has an internal combustion engine and an electric motor (rotating electric machine) as a prime mover. In Patent Document 1, an electric motor outputs torque to two input shafts of the dual clutch transmission (the output shafts of the first and second clutch shafts), so that the engine output shaft is driven to rotate. It has been proposed to perform an "ranking" and start the internal combustion engine.

  Patent Document 2 below includes an internal combustion engine (engine) and a motor (motor generator) as a prime mover (driving force generation source), and a clutch (engine clutch) provided between the engine and the motor. In a hybrid vehicle, when the internal combustion engine is started, the engine rotation speed, which is the rotation speed of the engine output shaft, is suppressed in order to prevent the torque fluctuation caused by the first explosion from being transmitted to the drive wheels as it is and causing the driving force fluctuation. A control technique for adjusting an engagement force (engagement force) of an engine clutch so that (actual engine speed) follows a target value is disclosed.

JP 2007-153335 A JP 2006-298078 A

  By the way, in a hybrid vehicle equipped with the dual clutch transmission as described above, EV traveling, which is vehicle traveling in which only mechanical power output from the electric motor is transmitted to the driving wheels to generate driving force, is performed. Can do. During EV travel (hereinafter referred to as EV travel), the first and second clutches are normally controlled in a released state. When the required driving force, which is the driving force required to be generated on the driving wheels, increases during EV traveling, or when the state of charge (SOC) of the secondary battery that supplies power to the electric motor decreases, the internal combustion engine When an engine start request is generated, it is necessary to start the internal combustion engine in response to the start request.

  When starting the internal combustion engine during such EV travel, the first clutch or the second clutch is engaged, and the rotor of the electric motor engaged with the drive wheel is engaged with the engine output shaft. At the same time, by increasing the torque generated in the rotor of the electric motor (hereinafter referred to as motor torque), part of the mechanical power output from the rotor is transmitted to the engine output shaft, and the engine output shaft is rotated. It is possible to perform so-called “push cranking”. By performing such cranking, it is possible to start the internal combustion engine while preventing the so-called “driving force loss” in which the driving force generated in the drive wheels temporarily becomes zero.

  When starting the internal combustion engine by performing such cranking, an input that directly engages the engine output shaft with the corresponding clutch being engaged among the first and second input shafts of the dual clutch transmission. The rotational speed of the shaft (hereinafter referred to as input rotational speed) is proportional to the rotational speed of the drive wheel, that is, the vehicle speed, and when the corresponding clutch is engaged, the drive wheel and the engine output shaft are connected to each other. It changes in accordance with the reduction gear ratio of the gear stage to be engaged (hereinafter referred to as the starting stage). If the input rotational speed is low, when the clutch is engaged to perform cranking, the rotational speed of the engine output shaft is a rotational speed range in which vibration such as resonance occurs in the internal combustion engine (hereinafter referred to as vibration rotational speed). The internal combustion engine may vibrate when firing. On the other hand, if the input rotational speed is high, when engaging the clutch for cranking, the rotational speed difference between the stationary engine output shaft and the input shaft is large, and the friction loss in the clutch is large. There is a risk of becoming.

  In addition, when starting the internal combustion engine during EV traveling, it is necessary to start the internal combustion engine immediately in response to the start request, such as when the required driving force increases, that is, responsiveness to the start request is required. In some cases, even if the actual start of the internal combustion engine is relatively delayed from the start request, such as when the SOC of the secondary battery falls below a preset judgment value, there is no problem. Some do not require responsiveness to requests.

  Therefore, in a hybrid vehicle in which the rotor of the electric motor is engaged with at least one of the two input shafts of the dual clutch transmission, when cranking is performed during EV traveling, the start of the internal combustion engine is in response to the start request. In consideration of whether or not responsiveness is required, it is necessary to determine the starting stage having the optimum reduction ratio and to be in the engaged state.

  The present invention has been made in view of the above, and considers whether or not the start of the internal combustion engine needs to be responsive to the start request when performing cranking during EV traveling. Thus, it is an object of the present invention to provide a hybrid vehicle control technique capable of determining a starting stage having an optimum reduction ratio.

  In order to achieve the above object, a hybrid vehicle according to the present invention has an internal combustion engine and an electric motor as a prime mover, and a first input shaft and drive wheels are provided by any one of a plurality of shift stages. A first transmission mechanism that can be engaged; a second transmission mechanism that can engage the second input shaft and the drive wheel by any one of a plurality of shift stages; and an internal combustion engine A first clutch capable of engaging the engine output shaft and the first input shaft, and a second clutch capable of engaging the engine output shaft and the second input shaft; A dual clutch transmission in which the rotor of the electric motor is engaged with at least one of the input shaft and the second input shaft, and a control capable of controlling the engagement / release state of the shift stages of the first and second transmission mechanisms And a hybrid vehicle comprising: a control means, When a start request for the internal combustion engine is generated during EV traveling in which only mechanical power output from the pneumatic motor is transmitted to the drive wheels to generate drive force, the start of the internal combustion engine responds to the start request. Responsiveness determining means for determining whether or not the engine is required and when starting the internal combustion engine depending on whether or not the engine is required to respond to the start request And a starting stage determining means for determining a starting stage which is a shift stage for engaging the engine output shaft and the drive wheels.

  In the hybrid vehicle described above, the responsiveness determination means is configured to start the internal combustion engine when a request for starting the internal combustion engine is generated in response to an increase in the required drive power that is required to be generated in the drive wheels. It may be determined that responsiveness is required for the start request.

  In the hybrid vehicle described above, the responsiveness determination means may start the internal combustion engine when the start request for the internal combustion engine is generated in response to a decrease in the storage state of the secondary battery that supplies power to the electric motor. It can be determined that responsiveness is not required.

  In the hybrid vehicle described above, the start stage determining means outputs the output from the electric motor immediately after the start of the internal combustion engine when it is determined that the start of the internal combustion engine requires responsiveness to the start request. The motor driving force that is the driving force that acts on the driving wheel when the mechanical power is transmitted to the driving wheel, and the driving force that acts on the driving wheel when the mechanical power output from the internal combustion engine is transmitted to the driving wheel. The gear position at which the required driving force can be achieved by the engine driving force can be determined as the starting gear.

  In the hybrid vehicle described above, the start stage determining means rotates the engine output shaft for starting the internal combustion engine when it is determined that the start of the internal combustion engine does not require responsiveness to the start request. When driving, the input rotational speed, which is the rotational speed of the corresponding input shaft of the first and second input shafts, does not fall within the vibration rotational speed range set in advance corresponding to the vibration of the internal combustion engine. Of these, the gear position with the smallest reduction ratio can be determined as the start gear.

  In the hybrid vehicle described above, the control means engages the clutch corresponding to the start stage among the first and second clutches, and increases the motor output, which is mechanical power output by the electric motor, The engine output shaft can be driven to rotate.

  According to the present invention, when a request for starting an internal combustion engine is generated during EV traveling, the response determination for determining whether the start of the internal combustion engine requires responsiveness to the start request. And a gear stage that engages the engine output shaft and the drive wheels when starting the internal combustion engine, depending on whether the start of the internal combustion engine requires responsiveness to the start request. Since the engine has a starting stage determining means for determining a certain starting stage, when starting the internal combustion engine during EV traveling, the starting stage for engaging the drive wheels and the engine output shaft is set in response to the start request. Whether or not responsiveness is necessary can be considered.

  Hereinafter, the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily assumed by those skilled in the art or those that are substantially the same.

  First, the structure of the hybrid vehicle which concerns on this embodiment is demonstrated using FIGS. 1-3. FIG. 1 is a schematic diagram showing a schematic configuration of a hybrid vehicle. FIG. 2 is a schematic diagram showing a structure of a dual clutch mechanism included in the dual clutch transmission. FIG. 3 is a schematic diagram showing the structure of a modified dual clutch mechanism.

  The hybrid vehicle 1 includes an internal combustion engine 5 and a motor generator 50 (hereinafter simply referred to as “electric motor”) that is an electric motor capable of generating electricity as a prime mover (power source) for rotationally driving the drive wheels 88. Yes. The electric motor 50 constitutes a drive device (10, 50) together with the dual clutch transmission 10. The drive device (10, 50) is coupled to the internal combustion engine 5 and mounted on the hybrid vehicle 1. The hybrid vehicle 1 includes an electronic control device (hereinafter simply referred to as “ECU”) 100 for a hybrid vehicle as control means for controlling the internal combustion engine 5, the electric motor 50, and the dual clutch transmission 10 in a coordinated manner. Is provided. The ECU 100 is provided with a ROM (not shown) as storage means for storing various control constants.

  The internal combustion engine 5 is a heat engine that converts fuel energy into mechanical power by combustion and outputs it, and is a piston reciprocating engine in which a piston 6 reciprocates in a cylinder. The internal combustion engine 5 includes a fuel injection device, an ignition device, and a throttle valve device (not shown). These devices are controlled by the ECU 100. The internal combustion engine 5 outputs the generated mechanical power from an engine output shaft (crankshaft) 8. The engine output shaft 8 is coupled to an input side of a dual clutch mechanism 20 of the dual clutch transmission 10 described later, for example, a clutch housing 14a (see FIG. 2). The ECU 100 can adjust the mechanical power output from the engine output shaft 8 of the internal combustion engine 5. The internal combustion engine 5 is provided with a crank angle sensor (not shown) that detects a rotational angle position (hereinafter referred to as a crank angle) of the engine output shaft 8, and sends a signal related to the crank angle to the ECU 100. Yes. A torque generated in the engine output shaft 8 by the operation of the internal combustion engine 5 (hereinafter referred to as engine torque) is controlled by the ECU 100.

  The electric motor 50 has a function as an electric motor that converts supplied electric power into mechanical power and outputs it, and a rotating electric machine that has a function as a generator that converts input mechanical power into electric power and recovers it. This is a so-called motor generator. The electric motor 50 is composed of a permanent magnet type AC synchronous motor, and receives a supply of three-phase AC power from an inverter 110, which will be described later, to form a rotating magnetic field, and a rotation that rotates by being attracted to the rotating magnetic field. The rotor 52 is a child, and mechanical power can be input and output from the rotor 52. The electric motor 50 is provided with a resolver (not shown) that detects the rotational angle position of the rotor 52, and sends a signal related to the rotational angle position of the rotor 52 to the ECU 100.

  The hybrid vehicle 1 is provided with an inverter 110 and a secondary battery 120 as a power supply device that supplies power to the electric motor 50. The inverter 110 is configured to convert DC power supplied from the secondary battery 120 into AC power and supply the AC power to the electric motor 50. The secondary battery 120 stores electric power supplied to the electric motor 50. The inverter 110 is also configured to be able to convert the AC power from the electric motor 50 into DC power and collect it in the secondary battery 120. Electric power supply from the inverter 110 to the electric motor 50 and power recovery from the electric motor 50 are controlled by the ECU 100.

  In the following description, the fact that the electric motor 50 functions as an electric motor and the electric motor 50 outputs mechanical power from the rotor 52 is referred to as “powering”. On the other hand, the electric motor 50 is made to function as a generator, and mechanical power transmitted from the driving wheel 88 to the rotor 52 of the electric motor 50 is converted into electric power and collected in the secondary battery 120. Braking the rotation of the rotor 52 and the member (for example, the drive wheel 88) engaged with the rotor 52 by the rotational resistance generated in the rotor 52 is referred to as “regenerative braking”. Switching of functions of the electric motor 50 as an electric motor / generator and torque input or output from the rotor 52 in the electric motor 50 (hereinafter referred to as motor torque) are controlled by the ECU 100.

  The hybrid vehicle 1 is a power transmission device that transmits mechanical power from the internal combustion engine 5 and the electric motor 50 to the drive wheels 88, and changes the torque by shifting the mechanical power from the engine output shaft 8 and the electric motor 50. The dual clutch transmission 10 capable of transmitting toward the propulsion shaft 66 engaged with the drive wheel 88, and the left and right engaging with the drive wheel 88 while decelerating the mechanical power transmitted to the propulsion shaft 66. And a final reduction gear 70 that distributes to the drive shaft 80.

  The dual clutch transmission 10 shifts the mechanical power received by the first input shaft 27 by any one of the first group of shift stages 31, 33, 35, 39 and engages with the drive wheels 88. The first transmission mechanism 30 that can be transmitted to the propulsion shaft 66 and the mechanical power received by the second input shaft 28 are shifted by one of the second gear stages 42 and 44 to drive wheels 88. And a second speed change mechanism 40 that can transmit to the propulsion shaft 66 that engages with the engine, and in addition, the engine output shaft 8 of the internal combustion engine 5 and the first input shaft 27 can be engaged with each other. The dual clutch mechanism 20 includes a first clutch 21 and a second clutch 22 capable of engaging the engine output shaft 8 and the second input shaft 28.

  The dual clutch transmission 10 has five shift stages from the first speed gear stage 31 to the fifth speed gear stage 35 for forward movement, and has one shift stage and a reverse gear stage 39 for backward movement. is doing. The reduction ratios of the first speed to the fifth speed gear stages 31 to 35 are as follows: the first speed gear stage 31, the second speed gear stage 42, the third speed gear stage 33, the fourth speed gear stage 44, and the fifth speed gear stage. It is set to decrease in the order of 35.

  The first speed change mechanism 30 is configured as a parallel shaft gear device having a plurality of gear pairs. The first group of shift speeds is an odd speed, that is, a first speed gear stage 31, a third speed gear stage 33, and the like. The fifth gear stage 35 and the reverse gear stage 39 are included. In the first speed change mechanism 30, the first speed gear 31 is the lowest speed among the forward shift speeds 31, 33, and 35.

  The first speed gear stage 31 is provided so as to be rotatable about a first output shaft 37 and a first speed main gear 31a coupled to the first input shaft 27, and is engaged with the first speed main gear 31a. Speed counter gear 31c. The first speed change mechanism 30 has a first speed coupling mechanism (mesh clutch mechanism) capable of engaging the first speed counter gear 31c and the first output shaft 37 corresponding to the first speed gear stage 31. ) 31e is provided. By engaging the first speed counter gear 31c and the first output shaft 37 by the first speed coupling mechanism 31e, that is, by bringing the first speed gear stage 31 into the engaged state, the first transmission mechanism 30 The mechanical power received by the input shaft 27 can be changed by the first speed gear 31 and the torque can be changed and transmitted to the first output shaft 37.

  Similarly, the third speed gear stage 33 is provided rotatably about a third speed main gear 33a coupled to the first input shaft 27 and a first output shaft 37, and the third speed main gear 33a And a third speed counter gear 33c that meshes. The first speed change mechanism 30 is provided with a third speed coupling mechanism 33e corresponding to the third speed gear stage 33 and capable of engaging the third speed counter gear 33c and the first output shaft 37. ing. By engaging the third speed counter gear 33c and the first output shaft 37 by the third speed coupling mechanism 33e, that is, by bringing the third speed gear stage 33 into the engaged state, the first transmission mechanism 30 The mechanical power received by the input shaft 27 can be shifted by the third speed gear stage 33, and the torque can be changed and transmitted to the first output shaft 37.

  The fifth speed gear stage 35 is provided so as to be rotatable about a first output shaft 37 and a fifth speed main gear 35a coupled to the first input shaft 27, and meshes with the fifth speed main gear 35a. And a fifth speed counter gear 35c. The first speed change mechanism 30 is provided with a fifth speed coupling mechanism 35e corresponding to the fifth speed gear stage 35 and capable of engaging the fifth speed counter gear 35c and the first output shaft 37. ing. By engaging the fifth speed counter gear 35c and the first output shaft 37 by the fifth speed coupling mechanism 35e, that is, by bringing the fifth speed gear stage 35 into the engaged state, the first transmission mechanism 30 The mechanical power received by the input shaft 27 can be shifted by the fifth speed gear stage 35, and the torque can be changed and transmitted to the first output shaft 37.

  The reverse gear stage 39 is engaged with the reverse main gear 39 a coupled to the first input shaft 27, the reverse intermediate gear 39 b meshed with the reverse main gear 39 a, and the reverse intermediate gear 39 b, and is centered on the first output shaft 37. And a reverse counter gear 39c provided rotatably. The first transmission mechanism 30 is provided with a reverse coupling mechanism 39e that can engage the reverse counter gear 39c and the first output shaft 37 corresponding to the reverse gear stage 39. The first transmission mechanism 30 is received from the first input shaft 27 by engaging the reverse counter gear 39c and the first output shaft 37 by the reverse coupling mechanism 39e, that is, by bringing the reverse gear stage 39 into the engaged state. The mechanical power can be transmitted to the first output shaft 37 by changing the rotation direction to the reverse direction and changing the speed by the reverse gear stage 39 and changing the torque.

  A first drive gear 37 c is coupled to the first output shaft 37 of the first transmission mechanism 30, and the first drive gear 37 c meshes with the power integration gear 58. A propulsion shaft 66 is coupled to the power integration gear 58. The propulsion shaft 66 is engaged with a drive shaft 80 to which drive wheels 88 are coupled via a final reduction gear 70 described later. In other words, the first output shaft 37 on the output side of the first gear stage 31, 33, 35, 39 of the first transmission mechanism 30 and the drive wheel 88 are engaged.

  Switching between the engaged state and the disengaged state (non-engaged state) of each of the gear stages 31, 33, 35, 39 in the first transmission mechanism 30 is controlled by the ECU 100 via an actuator (not shown). The ECU 100 selects any one of the first gear stages 31, 33, 35, 39 of the first transmission mechanism 30 to be in an engaged state, so that the first transmission mechanism 30 is in the first input shaft. The mechanical power received at 27 can be shifted by the selected gear stage and can be transmitted from the first output shaft 37 to the drive wheels 88.

  On the other hand, like the first transmission mechanism 30, the second transmission mechanism 40 is configured as a parallel shaft gear device having a plurality of gear pairs, and the second group of shift stages is an even stage, that is, the second speed. It comprises a gear stage 42 and a fourth speed gear stage 44. The rotor 52 of the electric motor 50 is coupled to the second input shaft 28 that is the input shaft of the second transmission mechanism 40.

  The second speed gear stage 42 is provided so as to be rotatable about a second output shaft 48 and a second speed main gear 42a coupled to the second input shaft 28, and engages with the second speed main gear 42a. Speed counter gear 42c. The second speed change mechanism 40 is provided with a second speed coupling mechanism 42e corresponding to the second speed gear stage 42 and capable of engaging the second speed counter gear 42c and the second output shaft 48. ing. By engaging the second speed counter gear 42c and the second output shaft 48 by the second speed coupling mechanism 42e, that is, by bringing the second speed gear stage 42 into the engaged state, the second speed change mechanism 40 is The mechanical power received by the two input shafts 28 can be shifted by the second gear stage 42, and the torque can be changed and transmitted to the second output shaft 48.

  Similarly, the fourth speed gear stage 44 is provided so as to be rotatable about a fourth speed main gear 44a coupled to the second input shaft 28 and a second output shaft 48, and is connected to the fourth speed main gear 44a. And a fourth speed counter gear 44c that meshes. The second speed change mechanism 40 is provided with a fourth speed coupling mechanism 44e corresponding to the fourth speed gear stage 44 and capable of engaging the fourth speed counter gear 44c and the second output shaft 48. ing. By engaging the fourth speed counter gear 44c and the second output shaft 48 by the fourth speed coupling mechanism 44e, that is, by bringing the fourth speed gear stage 44 into the engaged state, the second transmission mechanism 40 is The mechanical power received by the two input shafts 28 can be shifted by the fourth gear stage 44 and the torque can be changed and transmitted to the second output shaft 48.

  A second drive gear 48 c is coupled to the second output shaft 48 of the second speed change mechanism 40, and the second drive gear 48 c meshes with the power integration gear 58. A propulsion shaft 66 is coupled to the power integrated gear 58, and the propulsion shaft 66 is engaged with a drive shaft 80 coupled to a drive wheel 88 via a final reduction gear 70 described later. That is, the drive wheels 88 are engaged with the second output shaft 48 that constitutes the output side of the second gear stages 42 and 44 of the second transmission mechanism 40.

  The rotor 52 of the electric motor 50 is coupled to the second input shaft 28 of the second transmission mechanism 40, and mechanical power, that is, torque input / output from the rotor 52 is applied to the second input shaft 28 of the second transmission mechanism 40. It is transmitted as it is. That is, of the first input shaft 27 and the second input shaft 28 provided corresponding to the first transmission mechanism 30 and the second transmission mechanism 40 constituting the dual clutch transmission 10, respectively, The rotor 52 of the electric motor 50 is engaged.

  Switching between the engaged state and the disengaged state (non-engaged state) of the respective speed stages 42 and 44 in the second transmission mechanism 40 is controlled by the ECU 100 via an actuator (not shown). The ECU 100 selects one of the second speed stages 42 and 44 of the second speed change mechanism 40 and puts it in the engaged state, so that the second speed change mechanism 40 is connected to the second input shaft 28. The received mechanical power can be changed by the selected gear stage and can be transmitted from the second output shaft 48 to the drive wheels 88.

  The dual clutch mechanism 20 includes a first clutch 21 capable of engaging the engine output shaft 8 of the internal combustion engine 5 and the first input shaft 27 of the first transmission mechanism 30, and the engine output shaft 8 of the internal combustion engine 5. The second clutch 22 capable of engaging with the second input shaft 28 of the second transmission mechanism 40 is provided. The first clutch 21 and the second clutch 22 are constituted by a friction type disk clutch device such as a wet multi-plate clutch or a dry single-plate clutch.

  When the first clutch 21 is engaged, the engine output shaft 8 and the first input shaft 27 rotate together, and mechanical power from the engine output shaft 8 is transmitted to the gear stage 31 of the first transmission mechanism 30. , 33, 35, and 39, the speed can be changed and transmitted to the drive wheel 88. That is, the first clutch 21 is provided corresponding to the first group of gears 31, 33, 35, 39 of the first transmission mechanism 30.

  On the other hand, by bringing the second clutch 22 into the engaged state, the engine output shaft 8 and the second input shaft 28 rotate integrally, and mechanical power from the engine output shaft 8 is shifted by the second transmission mechanism 40. The speed can be changed by one of the stages 42 and 44 and transmitted to the driving wheel 88. In other words, the second clutch 22 is provided corresponding to the second gear stages 42 and 44 of the second transmission mechanism 40.

  Switching between the engaged state and the released state (non-engaged state) of the first clutch 21 and the second clutch 22 is controlled by the ECU 100 via an actuator (not shown). In the dual clutch mechanism 20, the ECU 100 sets the mechanical power from the internal combustion engine 5 to the first clutch 21 or the second clutch 22 by engaging one and releasing the other. Transmission to either one of the first transmission mechanism 30 and the second transmission mechanism 40 is possible.

  Here, an example of a detailed structure of the dual clutch mechanism 20 will be described with reference to FIG. As shown in FIG. 2, in the dual clutch mechanism 20, a clutch housing 14 a of the dual clutch mechanism 20 is coupled to the engine output shaft 8 via a damper or the like (not shown). That is, the clutch housing 14a rotates integrally with the engine output shaft 8. The clutch housing 14a is configured to accommodate friction plates (clutch disks) 27a and 28a.

  On the other hand, the first input shaft 27 of the first transmission mechanism 30 and the second input shaft 28 of the second transmission mechanism 40 are arranged coaxially and have a double shaft structure. Specifically, the first input shaft 27 is configured as a hollow shaft, and the second input shaft 28 extends into the first input shaft 27. The second input shaft 28 that is an inner shaft is configured to be longer in the axial direction than the first input shaft 27 that is an outer shaft. First, main gears 31a, 33a, 35a, 39a of the respective speed stages of the first transmission mechanism 30 are arranged from the engine output shaft 8 side toward the drive wheel 88 side, and then the second transmission mechanism 40 is arranged. The main gears 42a and 44a of the respective shift stages are arranged.

  A disc-shaped friction plate 27 a is coupled to the end of the first input shaft 27, while a similar friction plate 28 a is coupled to the end of the second input shaft 28. The first clutch 21 has a friction counterpart plate (not shown) provided to face the friction plate 27a, and an actuator (not shown) that drives the friction counterpart plate. The first clutch 21 engages the engine output shaft 8 and the first input shaft 27 of the first transmission mechanism 30 by the friction counterpart plate pressing the friction plate 27a against the member coupled to the clutch housing 14a. Is possible.

  Similarly, the second clutch 22 is configured such that a friction mating plate (not shown) provided opposite to the friction plate 28a presses the friction plate 28a against a member coupled to the clutch housing 14a, so that the engine output The shaft 8 can be engaged with the second input shaft 28 of the second transmission mechanism 40. In the dual clutch mechanism 20, the driving of the friction counterpart plates provided corresponding to the first and second clutches 21 and 22 by the actuator is controlled by the ECU 100.

  In the detailed structure of the dual clutch mechanism 20 described above, the first input shaft 27 of the first transmission mechanism 30 and the second input shaft 28 of the second transmission mechanism 40 are arranged coaxially. The detailed structure of the mechanism 20 is not limited to this. For example, as shown in FIG. 3, the first input shaft 27 and the second input shaft 28 may be arranged to extend in parallel with a predetermined interval. In the dual clutch mechanism 20 of this modification, a drive gear 14 c is coupled to the end of the engine output shaft 8. The first gear 16 and the second gear 18 are meshed with the drive gear 14 c, the first gear 16 is coupled to the first clutch 21, and the second gear 18 is coupled to the second clutch 22. ing. The first clutch 21 is configured to be able to engage the first input shaft 27 of the first transmission mechanism 30 and the first gear 16 that engages with the engine output shaft 8. On the other hand, the second clutch 22 is configured to be able to engage the second input shaft 28 of the second transmission mechanism 40 and the second gear 18 that engages with the engine output shaft 8.

  Each of the first and second clutches 21 and 22 can be configured by an arbitrary clutch mechanism such as a friction clutch. By alternately switching the engaged state and the released state in the first clutch 21 and the second clutch 22, the mechanical power of the internal combustion engine 5 output from the engine output shaft 8 is transferred from the drive gear 14c to the first transmission mechanism. It is transmitted to either the 30 first input shaft 27 or the second input shaft 28 of the second speed change mechanism 40.

  Further, as shown in FIG. 1, the hybrid vehicle 1 decelerates mechanical power transmitted from the prime mover to the propulsion shaft 66 and distributes it to the left and right drive shafts 80 engaged with the drive wheels 88. A device 70 is provided. The final reduction gear 70 includes a drive pinion 68 coupled to the propulsion shaft 66, and a differential mechanism 74 in which the drive pinion 68 and the ring gear 72 mesh with each other at right angles. The final reduction gear 70 decelerates the mechanical power transmitted to the propulsion shaft 66 from at least one of the prime mover, that is, the internal combustion engine 5 and the electric motor 50, by the drive pinion 68 and the ring gear 72, and the right and left by the differential mechanism 74. By distributing to the drive shaft 80 and transmitting it to the drive wheels 88 coupled to the drive shaft 80, it is possible to generate a drive force [N] for driving the hybrid vehicle 1 on the ground contact surface of the drive wheels 88. It has become.

  Further, the hybrid vehicle 1 is provided with a wheel speed sensor (not shown) that detects the rotational speed of the drive wheels 88, and sends a signal related to the detected rotational speed of the drive wheels 88 to the ECU 100. In addition, the hybrid vehicle 1 is provided with a battery monitoring unit (not shown) that detects a state-of-charge (SOC) of the secondary battery 120 that stores electric power supplied to the electric motor 50. Thus, the detected signal related to the storage state of the secondary battery 120 is sent to the ECU 100. Further, the hybrid vehicle 1 is provided with an accelerator pedal position sensor (not shown) that detects the amount of operation of the accelerator pedal by the driver, and relates to the amount of operation of the accelerator pedal (hereinafter referred to as accelerator operation amount). A signal is sent to the ECU 100.

  The ECU 100 detects the engagement / release state of each shift stage in the first transmission mechanism 30 and the second transmission mechanism 40 and the engagement / release state of the first clutch 21 and the second clutch 22. The ECU 100 also includes a signal related to the rotational angle position (crank angle) of the engine output shaft 8 from a crank angle sensor (not shown), a signal related to the rotational angle position of the rotor 52 of the electric motor 50 from the resolver, A signal related to the rotational speed of the drive wheel 88 from the wheel speed sensor is detected. The ECU 100 detects a signal related to the SOC of the secondary battery 120 from the battery monitoring unit and a signal related to the accelerator operation amount from the accelerator pedal position sensor.

  Based on these detected signals, ECU 100 calculates various control variables. The control variables include the rotational speed of the engine output shaft 8 of the internal combustion engine 5 (hereinafter referred to as engine rotational speed), the “engine torque” output from the engine output shaft 8 by the internal combustion engine 5, and the rotor 52 of the electric motor 50. , The "motor torque" generated in the rotor 52 of the electric motor 50, the engaged / released state of the first clutch 21 and the second clutch 22, and the first transmission mechanism 30. The second speed change mechanism 40 is currently selected (engaged), the travel speed of the hybrid vehicle 1 (hereinafter referred to as vehicle speed), the SOC of the secondary battery 120, and the driver. A driving force required to be generated in the shaft 80 (hereinafter referred to as a required driving force) is included.

  Based on these control variables, the ECU 100 grasps the operation of the internal combustion engine 5 and the electric motor 50, and the ECU 100 operates the internal combustion engine 5, that is, the engine rotation speed and the engine torque, and the operation state of the electric motor 50. That is, the motor rotation speed and the motor torque, the engagement / release state of the first clutch 21 and the second clutch 22, and the engagement / release of the gear stages 31 to 44 of the first transmission mechanism 30 and the second transmission mechanism 40. It is possible to control the state in a coordinated manner.

  In the hybrid vehicle 1 configured as described above, the mechanical power from the engine output shaft 8 of the internal combustion engine 5 is applied to the drive wheels 88 by alternately engaging the first clutch 21 and the second clutch 22. When switching the speed stage (engine output speed stage) used for power transmission to be transmitted between the speed stages 31, 33, 35 of the first speed change mechanism 30 and the speed stages 42, 44 of the second speed change mechanism 40, It is possible to prevent the power transmission from the engine output shaft 8 to the drive wheels 88 from being interrupted.

  For example, when performing an upshift to switch the engine output gear stage from the first speed gear stage 31 of the first transmission mechanism 30 to the second speed gear stage 42 of the second transmission mechanism 40, the first clutch 21 is engaged. When the second clutch 22 is in the disengaged state, the second input shaft 28 is idled by previously engaging the second speed gear stage 42. An operation of switching the first clutch 21 and the second clutch 22 by bringing the second clutch 22 to be released into the engaged state while putting the first clutch 21 in the engaged state into a released state, so-called “Clutch to clutch” is performed. As a result, the power transmission path from the engine output shaft 8 to the propulsion shaft 66 is gradually moved from the first input shaft 27 of the first transmission mechanism 30 to the second input shaft 28 of the second transmission mechanism 40. The upshift from the speed gear stage 31 to the second speed gear stage 42 is completed. In this way, the dual clutch type transmission 10 does not interrupt the transmission of power from the engine output shaft 8 to the drive wheels 88, and the second speed change mechanism, that is, the speed change stage of the first speed change mechanism 30, that is, the second speed change mechanism. A shift operation for switching the engine output gear stage can be performed between 40 gear stages, i.e., even stages.

  Moreover, the hybrid vehicle 1 can implement | achieve various vehicle driving | running | working (running modes) by using together or selectively using the internal combustion engine 5 and the electric motor 50 as a motor. For example, “engine running”, which is a vehicle running in which a driving force is generated in the driving wheel 88 by transmitting only mechanical power (engine output) output from the engine output shaft 8 of the internal combustion engine 5 to the driving wheel 88; The mechanical power output from the engine output shaft 8 of the engine 5 and the mechanical power output from the rotor 52 of the electric motor 50 are integrated and transmitted to the drive wheels 88 to generate a drive force on the drive wheels 88. “HV traveling”, which is a vehicle traveling that causes the driving wheels 88 to generate a driving force by transmitting only the mechanical power output from the rotor 52 of the electric motor 50 to the driving wheels 88. Etc.

  These vehicle travels are automatically and sequentially performed by the ECU 100 in accordance with the required driving force required to be generated on the driving wheels by the driver and the SOC of the secondary battery 120 that stores the power supplied to the electric motor 50. Switched. Hereinafter, the control of the ECU 100 in each travel mode and the operations of the internal combustion engine 5, the first clutch 21 and the second clutch 22, the first transmission mechanism 30, the second transmission mechanism 40, and the electric motor 50 will be described together.

  The ECU 100 causes the first clutch 21 to be in an engaged state and the second clutch 22 to be in a released state, so that the dual clutch transmission 10 receives mechanical power from the engine output shaft 8 of the internal combustion engine 5 as the first power. 1 is received by one input shaft 27, and is shifted by one of the shift stages 31, 33, 35, 39 of the first transmission mechanism 30 and is transmitted from the first output shaft 37 to the drive wheels 88. be able to. Thus, the hybrid vehicle 1 can realize engine running when the first clutch 21 is engaged.

  In this case, the second input shaft 28 is proportional to the rotational speed of the drive wheels 88, that is, the vehicle speed of the hybrid vehicle 1 by engaging any one of the shift stages 42 and 44 of the second transmission mechanism 40. Idling at a rotating speed. At this time, the ECU 100 causes the electric motor 50 to power and output motor torque from the rotor 52 to the second input shaft 28, whereby the dual clutch transmission 10 is mechanically driven from the engine output shaft 8 of the internal combustion engine 5. The motive power and the mechanical power from the rotor 52 of the electric motor 50 are shifted by the gear position engaged in the first transmission mechanism 30 and the gear position engaged in the second transmission mechanism 40, respectively. It can be integrated by the power integration gear 58 and transmitted to the drive wheel 88. In this way, the hybrid vehicle 1 can achieve HV traveling when the first clutch 21 is engaged.

  On the other hand, the ECU 100 causes the first clutch 21 to be in the released state and the second clutch 22 to be in the engaged state, so that the dual clutch transmission 10 receives mechanical power from the engine output shaft 8 of the internal combustion engine 5, It can be received by the second input shaft 28, can be shifted by the gear stage in the engaged state of any one of the gear stages 42 and 44 of the second transmission mechanism 40, and can be transmitted from the second output shaft 48 to the drive wheels 88. . In this way, the hybrid vehicle 1 can realize engine running when the second clutch 22 is in an engaged state.

  In this case, the ECU 100 causes the electric motor 50 to power and output motor torque from the rotor 52 to the second input shaft 28, so that the dual clutch transmission 10 is mechanically powered from the rotor 52 of the electric motor 50. And the mechanical power from the engine output shaft 8 of the internal combustion engine 5 are integrated by the second input shaft 28, and the second transmission mechanism 40 is shifted by the gear stage in the engaged state, and the power integrated gear 58 is To the drive wheel 88. In this way, the hybrid vehicle 1 can achieve HV traveling when the second clutch 22 is engaged.

  Further, when the hybrid vehicle 1 performs EV traveling that selectively uses only the electric motor 50 as a prime mover, unlike the above-described engine traveling and HV traveling control, the ECU 100 uses both the first clutch 21 and the second clutch 22. Both are brought into a released state, and one of the gear stages 42 and 44 of the second transmission mechanism 40 is brought into an engaged state to cause the electric motor 50 to power. The dual clutch transmission 10 receives mechanical power from the rotor 52 of the electric motor 50 (hereinafter referred to as “motor output”) by the second input shaft 28 and is in the engaged state in the second transmission mechanism 40. Is transmitted to the driving wheel 88 via the power integration gear 58.

  When the internal combustion engine 5 is started during such EV traveling, the first clutch 21 or the second clutch 22 is engaged and the rotor 52 of the electric motor 50 engaged with the drive wheel 88 and the engine output By engaging the shaft 8 and increasing the motor torque generated in the rotor 52 of the electric motor 50, a part of the motor output output from the rotor 52 is transmitted to the engine output shaft 8, and the engine output shaft It is possible to perform a so-called “push cranking” in which 8 is driven to rotate. When such push cranking is performed, after all the shift stages 42 and 44 of the second transmission mechanism 40 are released, the second clutch 22 is engaged and the electric motor 50 is powered to operate the engine. Compared with the case of performing “normal cranking” for rotationally driving the output shaft 8, the power transmission between the rotor 52 and the drive wheel 88 is cut off, so that the driving force temporarily becomes zero. It is possible to start the internal combustion engine 5 while preventing the occurrence of "".

  When the internal combustion engine 5 is started by performing such push cranking, the corresponding clutch of the first and second input shafts 27 and 28 of the dual clutch transmission 10 is engaged and the engine output is increased. The rotational speed of the input shaft that is directly engaged with the shaft 8 (hereinafter referred to as the input rotational speed) is proportional to the rotational speed of the drive wheels 88, that is, the vehicle speed, and when the corresponding clutch is engaged. The speed changes in accordance with a reduction gear ratio of a gear stage (hereinafter referred to as a start stage) that engages the drive wheel 88 with the engine output shaft 8. If the input rotational speed is low, the rotational speed of the engine output shaft 8 is a rotational speed range in which vibration such as resonance occurs in the internal combustion engine 5 when the clutch is engaged when performing push cranking (hereinafter referred to as the rotational speed range). The internal combustion engine may vibrate when firing. On the other hand, if the input rotational speed is high, the difference in rotational speed between the stationary engine output shaft 8 and the input shaft is large when the clutch engaging operation for push cranking is performed. Loss may increase.

  During such EV traveling, the ECU 100 may generate a control command (hereinafter referred to as a start request) for starting the internal combustion engine 5 in a non-operating state. When the amount of accelerator operation by the driver increases, the required driving force required to be generated in the driving wheel 88 increases, and only the motor output output from the rotor 52 by the electric motor 50 is transmitted to the driving wheel 88. Therefore, it is determined that the required driving force cannot be achieved, and the ECU 100 generates a request for starting the internal combustion engine 5 in accordance with the increase in the required driving force. Further, when the EV traveling is continued for a relatively long time and the SOC of the secondary battery 120 is lower than a predetermined determination value, the electric motor 50 is operated as a generator to increase the SOC of the secondary battery 120. The ECU 100 makes a request to start the internal combustion engine 5 in accordance with the decrease in the SOC of the secondary battery 120. When such a start request is generated, the ECU 100 executes “start control” for starting the internal combustion engine 5.

  In the start control, the ECU 100 is required to have a response (immediately performed) to the start request for the start of the internal combustion engine 5 executed by the start control. Or not (hereinafter simply referred to as “responsiveness determination means”). When a start request for the internal combustion engine 5 is generated in response to an increase in the required driving force, the ECU 100 determines that the start of the internal combustion engine 5 requires responsiveness to the start request. This is because the start of the internal combustion engine 5 and the achievement of the required drive force by the mechanical power from the internal combustion engine 5 are delayed with respect to the start request although the driver or the like intends to increase the required drive force. This is because the driver feels uncomfortable with driving performance.

  On the other hand, when a start request for the internal combustion engine 5 is generated in response to a decrease in the SOC of the secondary battery 120, the ECU 100 does not require that the start of the internal combustion engine 5 be responsive to the start request. judge. In order to raise the SOC of the secondary battery 120, the internal combustion engine 5 is started, and mechanical power from the internal combustion engine 5 is transmitted to the rotor 52 to operate the electric motor 50 as a generator. It is not necessary to start the internal combustion engine 10 immediately in response to the above, and the internal combustion engine 5 can be started when the traveling state of the hybrid vehicle 1 becomes a vehicle speed suitable for push cranking, that is, an input rotational speed. Because it is good.

  Therefore, in the hybrid vehicle 1 in which the rotor 52 of the electric motor 50 is engaged with at least one of the two input shafts 27 and 28 of the dual clutch transmission 10, when performing push cranking during EV traveling, the internal combustion engine In consideration of whether or not the start of the engine requires responsiveness to the start request, the start stage of the optimum reduction ratio according to the vehicle speed at the time when the clutch engagement operation is performed is determined, It is necessary to keep this in an engaged state.

  Therefore, in the hybrid vehicle 1 according to the present embodiment, the ECU 100 serving as the control means is responsive to the start request when the start of the internal combustion engine 5 occurs when the start request of the internal combustion engine 5 occurs during EV traveling. The conditions for determining the starting stage are changed, and will be described below with reference to FIGS. 1 and 4 to 9.

  FIG. 4 is a flowchart for explaining a method for obtaining the input rotation speed for the shift speed and the vehicle speed to be engaged and the vehicle speed and the lower limit value necessary for determining the start speed of the hybrid vehicle according to the present embodiment. FIG. 5 is a diagram showing the input rotational speed and the required starting power with respect to the vehicle speed for each shift speed in the hybrid vehicle according to the present embodiment. FIG. 6 is a flowchart showing start control executed by the control means (ECU) of the hybrid vehicle according to the present embodiment. FIGS. 7-1 is a figure explaining the power transmission path | route in a hybrid vehicle when the start control which concerns on this embodiment is performed, and is a figure which shows the case where a start stage is a 5th speed gear stage. FIG. 7-2 is a diagram illustrating a power transmission path in the hybrid vehicle when the start control according to the present embodiment is executed, and is a diagram illustrating a case where the start stage is the fourth speed gear stage. FIG. 8 is a flowchart showing the starting stage determination control based on the required driving force, which is executed by the control means (ECU) of the hybrid vehicle according to the present embodiment. FIG. 9 is a running performance curve diagram (driving force characteristic curve diagram) of the hybrid vehicle according to the present embodiment.

[Method of obtaining input rotation speed and lower limit input rotation speed]
In order to start the internal combustion engine 5 during EV traveling, the ECU 100 determines the shift stage (hereinafter referred to as the start stage) in which the engine output shaft 8 and the drive wheels 88 are engaged. The input rotation speed for each stage and vehicle speed and the lower limit value thereof are acquired as control parameters by the method described below.

As shown in FIG. 4, in step S000, the ECU 100 calculates an input rotation speed map indicating the input rotation speed Nc with respect to the gear position to be engaged and the vehicle speed. The input rotation speed Nc is the rotation speed of the first input shaft 27 when the gear position to be engaged is that of the first transmission mechanism 30, and when it is that of the second transmission mechanism 40, The rotational speed of the second input shaft 28 is obtained. That is, the input rotation speed Nc changes in proportion to the vehicle speed and the reduction gear ratio of the gear stage to be engaged. Specifically, first, the rotational speed (driving wheel rotational speed) Nd of the driving wheel 88 is obtained from the vehicle speed and the moving radius of the driving wheel 88. The ECU 100 determines, based on the drive wheel rotation speed Nd, the reduction ratio Rt of each shift stage, and the final reduction ratio Rd of the final reduction gear 70, for each of the shift stages 31 to 44 and the vehicle speed according to the following equation (1). An input rotation speed Nc is calculated.
Nc = Nd × Rd × Rt (1)

  Note that the speed reduction ratios of the gear stages 31, 33, and 35 of the first speed change mechanism 30 include the speed reduction ratio between the first drive gear 37c and the power integrated gear 58. The reduction ratios of the stages 42 and 44 include the reduction ratio between the second drive gear 48c and the power integrated gear 58.

In step S010, the ECU 100 calculates a required start power map indicating the required start power Pn with respect to the shift speed and the vehicle speed. The required starting power Pn is mechanical power that needs to be transmitted from the electric motor 50 to the engine output shaft 8 when starting the internal combustion engine 5, and the electric motor 50 is required to start the internal combustion engine 5. This is mechanical power that is output toward the output shaft 8. Based on the input rotational speed Nc and the maximum value T (hereinafter referred to as the maximum cranking torque) T of the torque required for rotational driving of the engine output shaft when starting the internal combustion engine 5, the ECU 100 According to 2), the required starting power Pn is calculated for each of the gears 31 to 44 and the vehicle speed.
Pn = T × Nc (2)

  The maximum cranking torque T is a torque that acts on the engine output shaft 8 by the compression reaction force in the vicinity of the compression top dead center of the internal combustion engine 5. The maximum cranking torque T is obtained in advance by a matching experiment or the like, and is stored in the ROM of the ECU 100 as a control constant.

  In step S020, the ECU 100 acquires a rotational speed region (hereinafter referred to as a vibration rotational speed region) of the engine output shaft 8 in which vibration such as resonance occurs in the internal combustion engine 5, as indicated by hatching in FIG. Set. The vibration rotation speed range is determined based on the specifications of the hybrid vehicle 1 such as a mount or a damper that supports the internal combustion engine 5. In the present embodiment, the vibration rotational speed region is a predetermined engine rotational speed region that is not related to the vehicle speed, as indicated by hatching in FIG. The minimum value of the vibration rotation speed region and the maximum value Nvmax (hereinafter referred to as the maximum vibration rotation speed) of the vibration rotation speed region are obtained in advance by a matching experiment or the like, and are stored in the ROM of the ECU 100 as control constants. .

  In the present embodiment, the vibration rotation speed range is constant regardless of the shift speed and the vehicle speed to be engaged, but is not limited to this mode. The ECU 100 may be set in accordance with parameters indicating the driving state of the hybrid vehicle 1 such as the gear position and the vehicle speed to be engaged.

In step S030, the ECU 100 starts the internal combustion engine 5, and particularly when the first explosion occurs in the internal combustion engine 5, the lower limit of the input rotational speed is set so that the engine rotational speed exceeds the above-described maximum vibration rotational speed Nvamx. A value Nmin (hereinafter referred to as a lower limit input rotation speed) is set by the following equation (3).
Nmin = Nvmax + A (3)
In Equation (3), A is a value set so as to allow a margin so that the input rotation speed does not enter the vibration rotation speed region.

  As described above, the ECU 100 acquires, as control variables, the input rotational speed for each shift speed and vehicle speed to be engaged and the lower limit input rotational speed Nmin.

[Starting control during EV travel]
Next, start control that is executed when the ECU 100 receives a start request for the internal combustion engine 5 during EV traveling will be described. When the ECU 100 receives a request for starting the internal combustion engine 5 during EV traveling, the ECU 100 first acquires various control variables in step S102 as shown in FIG. Among the control variables are vehicle speed, mechanical power Pev (hereinafter referred to as EV travel output) output from the electric motor 50 to the drive wheels 88 to perform EV travel, and forward shift stages 31 to 44. There are gears and the like that are engaged.

  In step S104, when starting the internal combustion engine 5, the ECU 100 can be used as a start stage for engaging the engine output shaft 8 and the drive wheels 88 without causing a drive force drop (hereinafter referred to as a shift stage). , Referred to as an available gear position).

  For example, as shown by a thick solid line in FIG. 7A, when EV traveling is performed with the fourth gear stage 44 engaged, the usable gear stage in the second transmission mechanism 40 is in the engaged state. There is only a certain fourth speed gear stage 44, and the second speed gear stage 42 does not become a usable gear position. To bring the second gear stage 42 into the engaged state, the motor torque is set to zero, the fourth gear stage 44 is released, and then the rotational speed of the second input shaft 28 is adjusted by the electric motor 50. The second speed gear stage 42 needs to be engaged, and the rotor of the electric motor 50 is between the start of the release operation of the fourth speed gear stage 44 and the completion of the engagement operation of the second speed gear stage 42. This is because power cannot be transmitted between the drive wheel 88 and the driving wheel 88, and so-called “driving force loss” occurs in which the driving force generated in the driving wheel 88 becomes zero.

  On the other hand, the available speeds in the first speed change mechanism 30 are all the forward speeds, that is, the first speed gear stage 31, the third speed gear stage 33, and the fifth speed gear stage 35. During EV traveling, both the first clutch 21 and the second clutch 22 are normally in a released state, and the first input shaft 27 is idling in the first transmission mechanism 30 and is engaged with the drive wheels 88. Torque does not act between the first output shaft 37 and the first input shaft 27. For this reason, in the first transmission mechanism 30, the gear stages 31, 33, and 35 can be easily engaged.

  Thus, when the hybrid vehicle 1 is performing EV traveling with the fourth gear stage 44 engaged, in the second transmission mechanism 40 in which the electric motor 50 is engaged with the second input shaft 28. In the first speed change mechanism 30 on the opposite side (non-motor side), the gear stage 44 that is currently in the engaged state becomes an available gear stage, and all the forward gear stages 31, 33, and 35 However, it becomes a usable gear position.

In step S106, the ECU 100 estimates a “startable output that can be generated” Pst that is mechanical power that can be generated by the electric motor 50 for cranking when the internal combustion engine 5 is started. The ECU 100 performs the following based on the maximum motor output Pmax, which is the maximum mechanical power that can be output by the electric motor 50, and the EV travel output Pev output by the electric motor 50 at the time when EV travel is being performed. The startable output Pst is estimated by the following equation (4).
Pst = Pmax−Pev (4)

  In step S108, the ECU 100 determines whether the start of the internal combustion engine 5 needs to be responsive to the start request. Specifically, it is determined whether it is necessary to start the internal combustion engine 5 immediately after receiving the start request, or whether there is no problem even if the actual start is relatively delayed from the start request.

  For example, when the required driving force increases with an increase in the amount of accelerator operation by the driver, the required driving force cannot be achieved due to an increase in the motor output of the electric motor 50, and a request for starting the internal combustion engine 5 occurs, the ECU 100 Since the internal combustion engine 5 must be started immediately and the required driving force must be achieved by the engine output from the internal combustion engine 5, the start of the internal combustion engine 5 needs to be responsive to the start request. Is determined. On the other hand, when the hybrid vehicle 1 continues the EV travel for a relatively long time and the SOC of the secondary battery 120 is lower than a predetermined determination value, and the start request for the internal combustion engine 5 is generated, the ECU 100 Assuming that there is no problem even if the internal combustion engine 5 is started after the vehicle speed reaches a value suitable for starting without immediately starting the internal combustion engine 5, the start of the internal combustion engine 5 is responsive to the start request. Judge that it is not necessary.

  When it is determined that the start of the internal combustion engine 5 does not require responsiveness to the start request (S108: No), such as when a start request is generated due to a decrease in the SOC of the secondary battery 120, the ECU 100 In step S110, “starting stage determination control based on vibration suppression and efficiency” is executed. Specifically, the required starting power Pn is equal to or less than the startable output Pst for starting, which is the difference between the maximum motor output Pmax and the EV travel output, from among the available shift speeds determined in step S104, and the input rotation The gear position at which the speed Nc is equal to or higher than the lower limit input rotation speed Nmin set in advance according to the vibration rotation speed range of the internal combustion engine 5 is specified according to the vehicle speed.

  For example, as shown in FIG. 5, a case will be described in which the hybrid vehicle 1 is performing EV traveling with the fourth gear stage 44 engaged and the vehicle speed is 50 km / h. When the fourth speed gear stage 44 is in the engaged state, the usable speed stages are the fourth speed gear stage 44 of the second transmission mechanism 40, the first speed gear stage 31 of the first transmission mechanism 30, and the third speed. The gear stage 33 and the fifth speed gear stage 35 are provided. Of these usable shift speeds 31, 33, 35, 44, the required shift power Pn is equal to or less than the startable output Pst and the input rotational speed Nc is equal to or higher than the lower limit input rotational speed Nmin ( As shown in FIG. 5, when the vehicle speed is 50 km / h, the third gear stage 33, the fourth gear stage 44, and the fifth gear stage 35 are provided.

  In other words, when the fourth speed gear stage 44 is engaged and EV traveling is performed and the vehicle speed is 50 km / h, if the specific speed stages 33, 44, and 35 are used, when the internal combustion engine 5 is started, It can be used as a starting stage without causing vibration such as resonance. Although the first speed gear stage 31 is a usable gear stage, the required starting power Pn proportional to the input rotational speed Nc exceeds the startable output Pst and cannot be used as the starting stage. The second gear stage 42 is not a usable gear stage, and if the gear stage 42 is used as a starting stage, the driving force is lost.

  The input rotational speed Nc is the lowest among the specific shift speeds 33, 44, and 35 where the required starting power Pn is equal to or less than the startable output Pst and the input rotational speed Nc is equal to or higher than the lower limit input rotational speed Nmin. The fifth gear stage 35, which is the gear stage having the smallest reduction ratio, is determined as the starting stage. In this way, the hybrid vehicle 1 performs EV traveling at the vehicle speed of 50 km / h with the fourth gear stage 44 engaged, and at this time, the start of the internal combustion engine 5 is in response to the start request. When it is determined that the responsiveness is not necessary, the ECU 100 executes “starting stage determination control based on vibration suppression and efficiency” and determines the fifth gear stage 35 as the starting stage.

  Then, in step S130, the ECU 100 determines whether or not the fifth speed gear stage 35, which is the determined starting stage, is currently engaged. For example, in the first speed change mechanism 30, when the third speed gear stage 33 is in the engaged state, the ECU 100 determines that the start stage is not currently in the engaged state (No), and in step S132, the start is started. The fifth speed gear stage 35 that is the stage is brought into an engaged state. Specifically, after the third speed gear stage 33 is released, the fifth speed gear stage 35 is engaged.

  In step S134, the ECU 100 engages the first clutch 21 corresponding to the fifth speed gear stage 35, which is the starting stage, as shown in FIG. The motor output of the electric motor 50 is increased by the necessary starting required power Pna (see FIG. 5). Accordingly, the mechanical power transmitted from the rotor 52 of the electric motor 50 to the driving wheel 88, which is indicated by a thick solid line in FIG. In addition, as shown by a thick broken line in the figure, the engine output shaft is connected from the rotor 52 via the power integration gear 58, the fifth speed gear stage 35 that is the starting stage, and the first clutch 21 that is the clutch corresponding to the starting stage. 8 can transmit the required starting power Pna to the engine, and the engine output shaft 8 can be rotationally driven at the input rotational speed Nca to perform cranking. By performing the firing while performing the cranking, the internal combustion engine 5 can be started without causing a driving force drop.

  On the other hand, when it is determined in step S108 that the start of the internal combustion engine 5 requires responsiveness to the start request (Yes), such as when a start request is generated due to an increase in the required driving force, the ECU 100 In step S120, “starting stage determination control based on required driving force” is executed.

  Specifically, as shown in step S <b> 121 of FIG. 8, the ECU 100 acquires a required driving force Ft required to be generated in the driving wheel 88 as a control variable. The required driving force Ft is calculated based on the accelerator operation amount and the vehicle speed by the driver.

  In step S122, as in step S110, the ECU 100 determines that the required starting power Pn is equal to or lower than the startable output Pst and the input rotational speed Nc is equal to or higher than the lower limit input rotational speed Nmin. Among the specific gears 33, 35, and 44 specified according to the vehicle speed (50 km / h), the fifth gear stage that is the smallest gear stage (that is, the gear stage that has the lowest input rotational speed). From 35, when this is set as the starting stage, whether or not the required driving force can be achieved immediately after the internal combustion engine 5 is started is examined by the following loop control.

In step S123, the ECU 100 determines a maximum driving force Fmax (hereinafter simply referred to as “maximum driving force”) that can be generated in the driving wheels 88 in accordance with the vehicle speed at that time. It is calculated from the fifth speed gear stage 35 with the smallest reduction ratio. The maximum driving force Fmax is a driving force that can transmit mechanical power that can be output from the internal combustion engine 5 to the driving wheel 88 by changing the torque at the start stage and changing the torque to the driving wheel 88. The “engine driving force” Fe and the motor torque that can be output from the electric motor 50 are changed according to the shift stage engaged with the second transmission mechanism 40 (they may coincide with the start stage) to change the torque Then, the total of the “motor driving force” Fmg, which is the driving force that can be transmitted to the driving wheel 88 and applied to the driving wheel 88, can be obtained by the following equation (5).
Fmax = Fe + Fmg (5)
That is, when the vehicle speed is the same, the engine driving force Fe increases as the starting speed is increased.

  In step S124, the ECU 100 determines whether or not the maximum driving force Fmax calculated according to the vehicle speed and the specific shift speed (fifth gear stage 35) exceeds the required driving force Ft. In other words, as shown in FIG. 9, it is determined whether or not the value obtained by subtracting the motor driving force Fmg from the required driving force Ft is smaller than the engine driving force Fe_5 when the fifth speed gear stage 35 is the starting stage. To do.

  As shown in FIG. 9, when the fifth speed gear stage 35 is set as the start stage, the ECU 100 determines that the maximum driving force Fmax is lower than the required driving force Ft (No), and proceeds to step S125, where The examination object is changed to the fourth gear stage 44, which is the specific gear stage having the next smallest reduction ratio after the gear stage 35.

  On the other hand, when the fourth speed gear stage 44 is set as the starting stage, as shown in FIG. 9, the engine driving force Fe_4 becomes larger than the value obtained by subtracting the motor driving force Fmg from the required driving force Ft. In this case, the ECU 100 determines that the maximum driving force Fmax when the fourth speed gear stage 44 is set as the starting stage is larger than the required driving force Ft (S124: Yes), and proceeds to step S126. The speed gear stage 44 is determined as the starting stage.

  In this way, the hybrid vehicle 1 performs EV traveling at the vehicle speed of 50 km / h with the fourth gear stage 44 engaged, and at this time, the start of the internal combustion engine 5 is in response to the start request. When it is determined that responsiveness is necessary, the ECU 100 executes “starting stage determination control based on the required driving force” and determines the fourth speed gear stage 44 as the starting stage.

  In step S130 shown in FIG. 6, the ECU 100 determines whether or not the fourth speed gear stage 44, which is the determined starting stage, is currently engaged. As shown in FIG. 7-2, when EV traveling is performed with the fourth gear stage 44 engaged, the ECU 100 determines that the starting stage is currently engaged (Yes). The process proceeds to step S134.

  In step S134, as shown in FIG. 7-2, the ECU 100 engages the second clutch 22 corresponding to the fourth speed gear stage 44, which is the starting stage, and rotationally drives the engine output shaft 8. The motor output of the electric motor 50 is increased by the necessary starting power Pnb (see FIG. 5) required for the operation. As a result, the mechanical power transmitted from the rotor 52 of the electric motor 50 to the drive wheels 88, which is indicated by a thick solid line in FIG. 7-2, is kept constant (that is, the drive force generated in the drive wheels 88 is kept constant). At the same time, as indicated by a thick broken line in the figure, the engine 52 requires the starting power Pnb (see FIG. 5) from the rotor 52 via the second input shaft 28 and the second clutch 22 corresponding to the starting stage 44. 5), and the engine output shaft 8 can be rotationally driven at the input rotational speed Ncb for cranking. By performing the firing during the cranking, the internal combustion engine 5 can be started and the required driving force Ft can be achieved immediately after the internal combustion engine 5 is started.

  As described above, the hybrid vehicle 1 according to the present embodiment includes the internal combustion engine 5 and the electric motor 50 as a prime mover, and the first vehicle is driven by any one of the plurality of shift stages 31, 33, 35, and 39. The first input shaft 27 and the drive wheels 88 can be engaged with each other, and the second input shaft 28 and the drive wheels 88 can be connected by any one of the plurality of shift stages 42 and 44. The second transmission mechanism 40 that can be engaged, the first clutch 21 that can engage the engine output shaft 8 and the first input shaft 27 of the internal combustion engine 5, the engine output shaft 8 and the first And the second clutch 22 capable of engaging with the two input shafts 28, and the rotor 52 of the electric motor 50 is engaged with at least one of the first input shaft 27 and the second input shaft 28. Dual clutch transmission 10 and first and second As a control means capable of controlling the engagement / release state of the speed stages 31 to 44 of the speed mechanisms 30 and 40, the engagement / release state of the first and second clutches 21 and 22, and the operation of the electric motor 50. An ECU 100 is provided.

  The ECU 100 starts the internal combustion engine 5 when a request for starting the internal combustion engine 5 is generated during EV traveling in which only mechanical power output from the electric motor 50 is transmitted to the drive wheels 88 to generate drive force. However, the function (responsiveness determination means) for determining whether or not responsiveness to the start request is required and the start of the internal combustion engine 5 require responsiveness to the start request. In accordance with whether or not the engine 5 is started, it has a function (starting stage determining means) for determining a starting stage which is a shift stage for engaging the engine output shaft 8 and the drive wheels 88. Therefore, when performing cranking for starting the internal combustion engine 5 during EV traveling, is the start stage for engaging the drive wheels 88 and the engine output shaft 8 required to be responsive to the start request? It can be considered whether or not.

  Further, in the present embodiment, the responsiveness determination means of the ECU 100 determines whether the internal combustion engine 5 is started when a request for starting the internal combustion engine 5 is generated in response to an increase in the required driving force that is required to be generated in the driving wheel 88. The start of the engine 5 is determined to require responsiveness to the start request. Although the driver or the like intends to increase the required drive force, the start of the internal combustion engine 5 and the achievement of the required drive force by the mechanical power from the internal combustion engine 5 are delayed with respect to the start request, and the operation is delayed. It can be suppressed that a feeling of discomfort related to drivability is given to a person.

  In the present embodiment, the responsiveness determination unit of the ECU 100 is configured such that when a request for starting the internal combustion engine 5 is generated in response to a decrease in the state of charge (SOC) of the secondary battery 120 that supplies power to the electric motor 50, The start of the internal combustion engine 5 is determined not to require responsiveness to the start request. In order to raise the SOC of the secondary battery 120, the internal combustion engine 5 is started, and mechanical power from the internal combustion engine 5 is transmitted to the rotor 52 to operate the electric motor 50 as a generator. It is not necessary to start the internal combustion engine 10 immediately in response to the vehicle speed, and the internal combustion engine 5 is started when the traveling state of the hybrid vehicle 1 becomes a vehicle speed suitable for push cranking, that is, the input rotational speed Nc. It becomes possible.

  In the present embodiment, when the start stage determining means of the ECU 100 determines that the start of the internal combustion engine 5 needs to be responsive to the start request, immediately after the start of the internal combustion engine 5, The mechanical power output from the electric motor 50 is transmitted to the drive wheels 88 and the motor drive force, which is the drive force acting on the drive wheels 88, and the mechanical power output from the internal combustion engine 5 is transmitted to the drive wheels 88. Thus, the gear position at which the required driving force can be achieved by the engine driving force that is the driving force acting on the driving wheel 88 is determined as the starting step. By engaging the start stage and engaging the clutch corresponding to the start stage, the engine output shaft 8 is rotationally driven to perform cranking to start the internal combustion engine 5. The required driving force can be achieved immediately after starting.

  In the present embodiment, the starting stage determining means of the ECU 100 determines the start of the internal combustion engine 5 at least when it determines that the start of the internal combustion engine 5 does not require responsiveness to the start request. When the engine output shaft 8 is rotationally driven, an input rotational speed Nc that is the rotational speed of the corresponding input shaft of the first and second input shafts 27 and 28 is set in advance corresponding to the vibration of the internal combustion engine 5. Of the gears that do not fall within the vibration rotation speed range (see FIG. 5), the gear with the smallest reduction ratio is determined as the starting gear, so when cranking is being performed (when firing) In other words, the occurrence of vibration such as resonance in the internal combustion engine 5 can be suppressed.

  Further, in the present embodiment, the ECU 100 is mechanical power that the electric motor 50 outputs from the rotor 52 while the clutch corresponding to the starting stage is engaged among the first and second clutches 21 and 22. The engine output shaft 8 is driven to rotate by increasing the motor output. A part of the increased motor output is transmitted to the engine output shaft 8 to rotationally drive the engine output shaft 8, so that when the internal combustion engine 5 is started, the machine is transmitted from the electric motor 50 to the drive wheels 88. It is possible to suppress a change in the dynamic power, that is, it is possible to suppress a change in the driving force generated in the driving wheel 88.

  In the present embodiment, the speed stages 42 and 44 of the second speed change mechanism 40, which is a speed change mechanism in which the rotor 52 of the electric motor 50 is engaged with the input shaft (second input shaft 28), are even speed stages (second speed). However, the aspect of the dual clutch transmission 10 to which the present invention can be applied is not limited to this. Of course, the gear stage of the second transmission mechanism 40 may be an odd-numbered stage, while the gear stage of the first transmission mechanism 30 may be an even-numbered stage.

  In the present embodiment, the electric motor 50 has a function as an electric motor that converts the supplied electric power into mechanical power and outputs the electric power, and a function as a generator that converts the input mechanical power into electric power. Although the motor generator is also provided, the electric motor according to the present invention is not limited to this. The electric motor 50 may be configured by an electric motor having only a function of converting electric power supplied from the secondary battery 120 into mechanical power and outputting it from the rotor 52.

  In each of the shift stages 31 to 44 of the first and second transmission mechanisms 30 and 40 according to the present embodiment, the main gears 31a to 44a are coupled to the first input shaft 27 or the second input shaft 28, respectively. The counter gears 31c to 44c that mesh with the main gears 31a to 44a are rotatably provided around the first output shaft 37 or the second output shaft 48, respectively, and the coupling mechanisms 31e to 44e are counter gears 31c to 44e. 44c and the output shafts 37 and 48 corresponding thereto are engaged, but the mode of the coupling mechanism is not limited to this. In at least some of the shift stages 31 to 44 of the first and second transmission mechanisms 30 and 40, a main gear is provided to be rotatable around an input shaft corresponding thereto, and a counter gear is provided. It may be coupled to the corresponding output shaft, and the coupling mechanism may engage the main gear and the input shaft.

  Further, in the present embodiment, the rotor 52 of the electric motor 50 is coupled to the second input shaft 28 of the second transmission mechanism 40, but the dual clutch transmission 10 to which the present invention is applicable can be applied. The embodiment is not limited to this. The second input shaft 28 only needs to be engaged with the rotor 52 of the electric motor 50. For example, the rotational speed of the rotor 52 is reduced between the second input shaft 28 and the rotor 52 to reduce the second input shaft. A speed reduction mechanism that transmits to the second input shaft 28 may be provided.

  Further, in the present embodiment, the dual clutch transmission 10 includes power integration in which the first transmission mechanism 30 engages mechanical power received by the first input shaft 27 with the drive wheels 88 from the first output shaft 37. The mechanical power transmitted by the second transmission mechanism 40 to the gear 58 and received by the second input shaft 28 is transmitted from the second output shaft 48 to the power integrated gear 58. The aspect of the second transmission mechanism 40 is not limited to this. The first speed change mechanism 30 and the second speed change mechanism 40 only need to be able to transmit the mechanical power received by the input shafts 27 and 28 to the drive wheels 88, for example, the first speed change mechanism 30 and the second speed change mechanism 40, for example. The speed change mechanism 40 may transmit mechanical power received by the first input shaft 27 and the second input shaft 28 to a common output shaft that engages with the drive wheels 88, respectively.

  In the present embodiment, the dual clutch transmission 10 transmits mechanical power from the engine output shaft 8 of the internal combustion engine 5 and the rotor 52 of the electric motor 50 to the first transmission mechanism 30 and the second transmission mechanism 40. Although the speed is changed by at least one and transmitted from the power integrated gear 58 to the drive wheel 88 via the propulsion shaft 66 and the differential mechanism 74 of the final reduction gear 70, the first speed change mechanism 30 and the second speed change mechanism The mode of power transmission from 40 to the drive wheel 88 is not limited to this. In the dual clutch transmission 10, the first transmission mechanism 30 and the second transmission mechanism 40 can transmit the mechanical power received by the first input shaft 27 and the second input shaft 28 to the drive wheels 88, respectively. For example, the power integrated gear 58 or the first and second drive gears 37 c and 48 c meshing with the power integrated gear 58 may directly drive the ring gear 72 of the differential mechanism 74.

  In the hybrid vehicle 1 according to the present embodiment, the rotor 52 of the electric motor 50 is engaged with at least one of the first input shaft 27 and the second input shaft 28 of the dual clutch transmission 10. However, the aspect of the hybrid vehicle 1 is not limited to this. When starting the internal combustion engine 5 during EV traveling, the first clutch 21 or the second clutch 22 is engaged, and the rotor 52 of the electric motor 50 engaged with the drive wheels 88, the engine output shaft 8, And the motor torque generated in the rotor 52 of the electric motor 50 is increased to transmit a part of the motor output output from the rotor 52 to the engine output shaft 8 to rotate the engine output shaft 8. For example, the motor has first and second electric motors as a prime mover, and the first input shaft of the dual clutch transmission 10 is engaged with the rotor of the first electric motor. The second input shaft may be engaged with the rotor of the second electric motor.

  Further, in this embodiment, when it is determined that the start of the internal combustion engine 5 needs to be responsive to the start request, the ECU 100 is in a usable shift stage that is a shift stage that can be used as the start stage. The internal combustion engine is selected from gears in which the required starting power Pn is equal to or less than the startable output Pst and the input rotational speed Nc is equal to or higher than the lower limit input rotational speed Nmin set according to the vibration rotational speed range. In this case, the gear position that can achieve the required driving force immediately after the start of the engine 5 is determined as the engine start stage. However, when it is determined that the start of the internal combustion engine 5 requires responsiveness to the engine start request. The method for determining the starting stage is not limited to this. A plurality of shift speeds that can achieve the required driving force immediately after the internal combustion engine 5 is started are identified from the available shift speeds, and the shift speed that is equal to or higher than the lower limit input rotational speed Nmin is selected from the plurality of shift speeds. Of these, the gear position having the smallest reduction ratio may be determined as the start gear.

  As described above, the present invention is useful for a hybrid vehicle including a dual clutch type transmission.

It is a mimetic diagram showing a schematic structure of a hybrid vehicle concerning this embodiment. It is a schematic diagram which shows the structure of the dual clutch mechanism which concerns on this embodiment. It is a schematic diagram which shows the structure of the dual clutch mechanism of the modification which concerns on this embodiment. It is a flowchart explaining the method of acquiring the input rotational speed with respect to the gear stage to be engaged, the vehicle speed, and the lower limit value necessary for determining the starting stage of the hybrid vehicle according to the present embodiment. It is a figure which shows the input rotational speed with respect to the vehicle speed for every gear stage, and required starting power in the hybrid vehicle which concerns on this embodiment. It is a flowchart which shows the starting control which the control means (ECU) of the hybrid vehicle which concerns on this embodiment performs. It is a figure explaining the power transmission path in a hybrid vehicle when starting control concerning this embodiment is performed, and is a figure showing the case where a starting stage is the 5th gear stage. It is a figure explaining the power transmission path in a hybrid vehicle when starting control concerning this embodiment is performed, and is a figure showing the case where a starting stage is the 4th speed gear stage. It is a flowchart which shows the starting stage determination control based on the request | requirement driving force which the control means (ECU) of the hybrid vehicle which concerns on this embodiment performs. It is a running performance curve figure (driving force characteristic curve figure) of a hybrid vehicle concerning this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 5 Internal combustion engine 8 Engine output shaft 10 Dual clutch type transmission 20 Dual clutch mechanism 21 1st clutch 22 2nd clutch 27 1st input shaft 28 2nd input shaft 30 1st speed change mechanism 31,33,35,39 Gear stage (shift stage, gear pair)
37 First output shaft 40 Second speed change mechanism 42, 44 Gear stage (gear stage, gear pair)
48 Second output shaft 50 Electric motor (motor generator)
52 Electric Motor Rotor 66 Propulsion Shaft 70 Final Deceleration Device 74 Differential Mechanism 80 Drive Shaft 88 Drive Wheel 100 Electronic Control Device for Hybrid Vehicle (ECU, Control Means, Storage Means, Response Judgment Means, Start Stage Determination Means)

Claims (6)

It has an internal combustion engine and an electric motor as a prime mover,
A first transmission mechanism capable of engaging the first input shaft and the drive wheel by any one of the plurality of shift speeds, and a second input shaft by any one of the plurality of shift speeds. A second speed change mechanism capable of engaging the drive wheel with the engine, a first clutch capable of engaging the engine output shaft and the first input shaft of the internal combustion engine, the engine output shaft and the second A dual clutch transmission having a second clutch capable of engaging with an input shaft, wherein the rotor of the electric motor is engaged with at least one of the first input shaft and the second input shaft;
Control means capable of controlling the engagement / release states of the shift stages of the first and second transmission mechanisms;
A hybrid vehicle with
The control means
When a start request for the internal combustion engine is generated during EV traveling in which only mechanical power output from the electric motor is transmitted to the drive wheels to generate a drive force, the start of the internal combustion engine responds to the start request. Responsivity determining means for determining whether or not the property is necessary;
Depending on whether or not the start of the internal combustion engine requires responsiveness to the start request, a start stage that is a shift stage for engaging the engine output shaft and the drive wheels when starting the internal combustion engine is provided. Starting stage determining means for determining;
A hybrid vehicle characterized by comprising: The hybrid vehicle according to claim 1,
The responsiveness determination means responds to the start request when the start request of the internal combustion engine is generated in response to an increase in the required drive force that is required to be generated in the drive wheel. The hybrid vehicle is characterized in that it is determined that it is necessary. In the hybrid vehicle according to claim 1 or 2,
The responsiveness determination means is responsive to the start request when the start request of the internal combustion engine occurs in response to a decrease in the storage state of the secondary battery that supplies power to the electric motor. A hybrid vehicle characterized by determining that it is not necessary. The hybrid vehicle according to any one of claims 1 to 3,
The starting stage determining means is
If it is determined that the start of the internal combustion engine requires responsiveness to the start request,
Immediately after starting the internal combustion engine, the mechanical power output from the electric motor is transmitted to the drive wheels and the motor drive force, which is the drive force acting on the drive wheels, and the mechanical power output from the internal combustion engine is applied to the drive wheels. A hybrid vehicle characterized in that a shift speed at which a required drive force can be achieved is determined as a start gear by an engine drive force that is transmitted and acts on drive wheels. In the hybrid vehicle according to any one of claims 1 to 4,
The starting stage determining means is
At least, when it is determined that the start of the internal combustion engine does not require responsiveness to the start request,
When the engine output shaft is rotationally driven for starting the internal combustion engine, the input rotational speed, which is the rotational speed of the corresponding input shaft of the first and second input shafts, is set in advance corresponding to the vibration of the internal combustion engine. A hybrid vehicle characterized in that, among the gears that do not fall within the vibration rotational speed range, the gear having the smallest reduction ratio is determined as the starting gear. In the hybrid vehicle according to any one of claims 1 to 5,
The control means
Of the first and second clutches, the clutch corresponding to the starting stage is engaged, and the motor output, which is mechanical power output by the electric motor, is increased to drive the engine output shaft to rotate. A hybrid vehicle.

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