FR3065421A1 - HYBRID VEHICLE - Google Patents

Abstract

Hybrid vehicle comprising a combustion engine and a converter unit serving as a driving source transmitting a motive force to a driving wheel, an automatic transmission for adapting a rotation coming out of the engine and transmitting it to the driving wheel, the automatic transmission comprising a disengaging clutch or driving a power transmission path between the automatic transmission and the engine, and a hybrid control unit, HCU, for controlling an assist torque delivered by the converter unit in an incomplete engagement period of the clutch according to a first a mode of travel or a second mode of movement, a shift control being automatically performed independently of an operation by an occupant in the first mode of movement, a shift control being effected according to an operation by the occupying the second mode of travel.

Description

® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(only to be used for reproduction orders) © National registration number

065 421

53517

COURBEVOIE © Int Cl ⁸ : B 60 W20 / 30 (2017.01)

PATENT INVENTION APPLICATION

A1

©) Date of filing: 20.04.18. © Priority: 21.04.17 JP 2017084397. © Applicant (s): SUZUKI MOTOR CORPORATION - JP. ©) Date of availability of the request: 26.10.18 Bulletin 18/43. @ Inventor (s): HAYAKAWA SHINICHIRO, HIGUCHI TORU and IKEDA KEISUKE. ©) List of documents cited in the preliminary search report: The latter was not established on the date of publication of the request. (© References to other related national documents: ® Holder (s): SUZUKI MOTOR CORPORATION. ©) Extension request (s): © Agent (s): CABINET PLASSERAUD. © HYBRID VEHICLE.

FR 3 065 421 - A1

Hybrid vehicle comprising a combustion engine and a converter unit serving as a driving source transmitting a driving force to a driving wheel, an automatic transmission for adapting a rotation coming out of the engine and transmitting it to the driving wheel, the automatic transmission comprising a declutching clutch or engaging a power transmission path between the automatic transmission and the engine, and a hybrid control unit, HCU, for controlling a torque assistance delivered by the converter group in a period of incomplete engagement of the clutch according to a first mode of travel or a second mode of travel, a speed change command being automatically performed independently of an operation by an occupant in the first mode of travel, a speed change command being performed depending on an operation by the occupying in the second mode of travel.

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The present invention relates to a hybrid vehicle.

JP 11-69 509 A describes a hybrid vehicle comprising an internal combustion engine and an electric motor as the driving source of the vehicle, and in which a clutch device is interposed between a stepped gearbox capable to perform an automatic gear change and the internal combustion engine. In this hybrid vehicle, the driving torque of the electric motor is increased simultaneously with a disengagement of the clutch device at the time of a gear change, in order to avoid a feeling of deceleration being felt during a shift of speed.

[0003] Incidentally, a constant speed movement command, to cause a vehicle to move at a constant speed independently of an acceleration / deceleration operation on the part of an occupant, and a tracking movement command, to automatically bring a vehicle to follow a vehicle which precedes it, are known under the name of “automatic displacement controls”, allowing to automatically control a displacement speed of a vehicle. When a technology disclosed in JP 11-69 509 A described above is applied to a vehicle performing such automatic movement control, the following problems arise.

[0004] During an automatic movement command, the speed of movement of the vehicle can be controlled even in the absence of any intention of an occupant to accelerate or decelerate the vehicle. Conversely, during a non-automatic movement command, the vehicle speed control is carried out following the occupant's intention to accelerate or decelerate the vehicle.

When the occupant has no intention of acceleration / deceleration during an automatic movement command, the acceleration / deceleration operation is performed on the basis of the intention of acceleration / deceleration of the occupant during a non-automatic movement command. This is why the feeling of idling during disengagement of a clutch device at the time of a gear change is different between an automatic movement control and a non-automatic movement control.

In addition, the energy of a battery is consumed each time an electric motor delivers an engine torque. This is why, when the engine torque is frequently delivered by the electric motor during a disengagement of the clutch device, as in the hybrid vehicle described in JP 11-69 509 A, there is a possibility that the battery power is insufficient.

When the energy of the battery is insufficient, there is a risk that the engine torque that can be delivered by the electric motor decreases, or that the engine torque cannot be delivered. The occupant may therefore be concerned that the sensation of idling will not be eliminated during a disengagement of the clutch device at the time of a gear change, which may cause unpleasant driving.

The present invention has been developed taking into account the above circumstances. An object of the present invention is to provide a hybrid vehicle capable of eliminating the sensation of idling during a period of incomplete engagement of a clutch at the time of a gear change following an intention of an occupant. .

According to aspects of the present invention, there is provided a hybrid vehicle comprising a combustion engine and an electric motor serving as a drive source transmitting power to a drive wheel, an automatic transmission for adapting rotation to the output of the engine and transmitting it to the drive wheel, the automatic transmission comprising a disengaging clutch or engaging a power transmission path between the automatic transmission and the engine, and a control member for controlling a torque assistance delivered by the electric motor in a incomplete clutch engagement period depending on whether a mode of movement of the hybrid vehicle is a first mode of travel or a second mode of travel, a gear change command being automatically performed independently of an operation by an occupant in the first mode of movement, a speed change command being zero carried out according to an operation by the occupant in the second mode of travel.

According to one embodiment, the first displacement mode is an automatic displacement mode in which a speed change command and a drive command are automatically carried out independently of the operation by the occupant to automatically effect a displacement in acceleration / deceleration.

According to one embodiment, in a case in which the mode of movement is the first mode of movement, the control member performs a control operation so that a value of the assistance torque is less than a corresponding value in a case in which the mode of travel is the second mode of travel.

According to one embodiment, the hybrid vehicle further comprises a vehicle speed detector for detecting a vehicle speed of the hybrid vehicle, and is produced so that when the assistance torque of a case where the mode of movement is the first mode of movement is defined as the first assistance torque, and the assistance torque of a case where the mode of travel is the second mode of travel is defined as the second assistance couple, l the control unit performs a control operation so that a ratio of the first assistance torque to the second assistance torque decreases as the vehicle speed detected by the speed detector increases vehicle.

According to one embodiment, when the mode of movement is the first mode of movement, the control member performs a control operation so that a value of the assistance torque is greater than a corresponding value in a case where the mode of displacement is the second mode of displacement.

According to one embodiment, the hybrid vehicle further comprises a vehicle speed detector for detecting a vehicle speed of the hybrid vehicle, and is produced so that when the assistance torque of a case where the mode of movement is the first mode of movement is defined as the first assistance torque, and the assistance torque of a case where the mode of travel is the second mode of travel is defined as the second assistance couple, l the control unit performs a control operation so that a ratio of the second assistance torque to the first assistance torque decreases as the vehicle speed detected by the speed detector increases vehicle.

According to one embodiment, the hybrid vehicle further comprises a battery for supplying energy to the electric motor, and is constructed so that, when a remaining capacity of the battery is less than a predetermined value, the member for control performs a control operation so that the electric motor delivers a different assistance torque in the period of incomplete engagement of the clutch between the first mode of movement and the second mode of movement.

According to the present invention, it is possible to provide a hybrid vehicle capable of eliminating the sensation of idling in a period of incomplete engagement of a clutch at the time of a gear change according to an intention of an occupant.

The present invention will be described in detail below with reference to the accompanying drawings in which:

Figure 1 is a configuration diagram of a hybrid vehicle according to a first embodiment of the present invention;

FIG. 2 is a flowchart illustrating a processing flow of an assistance torque output command carried out in the hybrid vehicle according to the first embodiment of the present invention;

Figure 3 is a time graph for describing an operation of the hybrid vehicle according to the first embodiment of the present invention;

FIG. 4 is a diagram illustrating an assistance torque adjustment card in a hybrid vehicle according to a second embodiment of the present invention;

FIG. 5 is a flow diagram illustrating a processing flow of an assistance torque output command carried out in a hybrid vehicle according to a third embodiment of the present invention;

Figure 6 is a time graph for describing an operation of the hybrid vehicle according to the third embodiment of the present invention; and FIG. 7 is a diagram illustrating an assistance torque adjustment card in a hybrid vehicle according to a fourth embodiment of the present invention.

A hybrid vehicle according to embodiments of the present invention comprises a combustion engine and an electric motor serving as a drive source transmitting power to a drive wheel, and an automatic transmission adapting engine torque and transmitting it to the wheel drive, the automatic transmission comprising a disengaging clutch or engaging a power transmission path between the automatic transmission and the engine. The hybrid vehicle further comprises a control member for controlling a torque assistance delivered by the electric motor in a period of incomplete engagement of the clutch depending on whether a mode of movement of the hybrid vehicle is a first mode of movement or a second mode of travel, a speed change command being automatically performed independently of an operation by an occupant in the first mode of travel, a speed change command being performed in accordance with an operation by the occupant in the second mode of travel. In this way, the hybrid vehicle according to the embodiments of the present invention can eliminate the sensation of idling in a period of incomplete engagement of a clutch when changing gear according to an intention of an occupant. .

First embodiment

A hybrid vehicle according to a first embodiment of the present invention will be described below with reference to the accompanying drawings.

As illustrated in Figure 1, a hybrid vehicle 1 comprises an engine 2 as an internal combustion engine, a transmission 3 as an automatic transmission, a converter unit 4 as an electric motor, a drive wheel 5, a hybrid control unit (HCU) 10 which controls the hybrid vehicle 1 overall, an engine control module (ECM) 11 which controls the engine 2, a transmission control module (TCM) 12 which controls the transmission 3, an integrated starter generator control module (ISGCM) 13, an inverter control module (INVCM) 14, a low voltage battery management system (BMS) 15, a high voltage BMS 16, and an adaptive cruise control (ACC) control member 17. The motor 2 and the converter unit 4 are included in a drive source which transmits power to the drive wheel 5.

The engine 2 includes several cylinders. In the present embodiment, the engine 2 is configured to perform a series of four strokes, namely an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke corresponding to each of the cylinders.

An integrated starter generator (ISG) 20 and a starter 21 are connected to the engine 2. The ISG 20 is connected to a crankshaft 18 of the engine 2 via a belt 22. The ISG 20 has an electric motor function which rotates while being supplied with energy to rotate the motor 2 and a generator function which converts a rotational force at the input from the crankshaft 18 into electric energy.

In this embodiment, the ISG 20 operates as an electric motor under the control of the ISGCM 13 to restart the motor 2 from a stopped state under an idle stop function. The ISG 20 can contribute to the movement of the hybrid vehicle 1 by operating as an electric motor.

The starter 21 includes an electric motor (not shown) and a pinion (not shown). The starter 21 rotates the electric motor to rotate the crankshaft 18, thereby supplying the motor 2 with rotational force upon start-up. In this way, the engine 2 is started by the starter 21 and is restarted by the ISG 20 from the stopped state under the idling stop function.

The transmission 3 changes the transmission ratio between the motor 2 and the drive wheel 5 via a drive shaft 23, thereby driving the drive wheel 5. The transmission 3 comprises a mechanism constant gear type transmission 25 comprising a parallel shaft gear mechanism, a clutch 26 comprising a normally closed type dry clutch, a differential mechanism 27, and actuators 51 and 52.

The clutch 26 is provided in a power transmission path between the transmission mechanism 25 and the engine 2 to disengage or engage the driving force transmission path.

The transmission 3 is configured as an automated manual transmission (AMT), in which a variable speed level in the transmission mechanism 25 is switched by the actuator 52 controlled by the TCM 12, and the clutch 26 is disengaged and engaged by the actuator 51. The differential mechanism 27 transmits power at the output of the transmission mechanism 25 to the drive shaft 23.

The converter group 4 is connected to the differential mechanism 27 by means of a power transmission mechanism 28, like a chain. The converter group 4 functions as an electric motor.

As described above, the hybrid vehicle 1 comprises a parallel hybrid system capable of using the driving force of the engine 2 and of the converter unit 4 to drive the vehicle, and it moves using the driving force delivered by at least one of the motor 2 and of the converter group 4.

The converter group 4 operates as a generator and generates energy by moving the hybrid vehicle 1. The converter group 4 can be connected to any part of a power transmission path between the engine 2 and the drive wheel 5, so that the converter unit 4 can transmit energy, without necessarily being connected to the differential mechanism 27.

The hybrid vehicle 1 comprises a first energy storage device 30, a low voltage power supply unit 32 comprising a second energy storage device 31, a high voltage power supply unit 34 comprising a third energy storage device 33 as a battery, a high voltage cable 35, and a low voltage cable 36.

The first energy storage device 30, the second energy storage device 31, and the third energy storage device 33 include rechargeable secondary batteries. The first energy storage device 30 consists of a lead-acid battery. The second energy storage device 31 is an energy storage device whose output and energy density are greater than those of the first energy storage device 30.

The second energy storage device 31 can be charged in less time than the first energy storage device 30. In the present embodiment, the second energy storage device 31 consists of a lithium battery. The second energy storage device 31 can be a nickel-hydrogen battery.

The first energy storage device 30 and the second energy storage device 31 are low-voltage batteries in which the number of cells, among others, is adjusted so that an output voltage of approximately 12 volts is generated. For example, the third energy storage device 33 consists of a lithium ion battery.

The third energy storage device 33 is a high-voltage battery in which the number of cells, among others, is adjusted so as to generate a voltage greater than the voltage of the first energy storage device 30 and at the voltage of the second energy storage device 31. For example, the third energy storage device 33 generates an output voltage of 100 volts. A remaining capacity state (referred to below as "remaining battery capacity") of the third energy storage device 33 is managed by a high voltage BMS 16.

A general charge 37 and a protected charge 38 are provided in the hybrid vehicle 1 as being electric charges. The general charge 37 and the protected charge 38 are electrical charges other than the starter 21 and the ISG 20.

The protected charge 38 is an electrical charge which constantly requires a stable electrical supply. The protected load 38 comprises a stability control device 38A preventing any skidding of the hybrid vehicle 1, an electric power steering control device 38B which contributes electrically to an actuating force of a steering wheel, and a headlight 38C. Protected load 38 includes indicators and counters for a dashboard (not shown) and a car navigation system (not shown).

The general load 37 is an electrical load which is temporarily used without requiring a stable electrical supply in comparison with the protected load 38. For example, the general load 37 comprises a wiper (not illustrated) and a cooling fan electric (not shown) which blows cooling air to the engine 2.

The low voltage power supply 32 includes switches 40 and 41 and the low voltage BMS 15 in addition to the second energy storage device 31. The first energy storage device 30 and the second device of energy storage 31 are connected to the starter 21, to the ISG 20, as well as to the general load 37 and to the protected load 38 as electrical loads via the low voltage cable 36, so that energy storage devices can provide them with energy. The first energy storage device 30 and the second energy storage device 31 are electrically connected to the protected load 38 in parallel.

The switch 40 is provided on the low voltage cable 36 between the second energy storage device 31 and the protected load 38. The switch 41 is provided on the low voltage cable 36 between the first storage device d energy 30 and the protected load 38.

The low voltage BMS 15 controls the loading and unloading of the second energy storage device 31 and the electrical supply of the protected load 38 by controlling the opening and closing of the switches 40 and 41. When the motor 2 is stopped by an idle stop, the low voltage BMS 15 closes the switch 40 and opens the switch 41, thereby supplying energy from the second energy storage device 31, which has a relatively high output and energy density at protected load 38.

When the engine 2 is started by the starter 21 and when the engine 2, stopped by an idle stop command, is restarted by the ISG 20, the low voltage BMS 15 closes the switch 40 and opens the switch 41, thereby supplying power from the first energy storage device 30 to the starter 21 or to the ISG 20. In the state in which the switch 40 is closed and the switch 41 is open , the energy is supplied from the first energy storage device 30 to the general load 37.

In this way, the first energy storage device 30 supplies energy at least to the starter 21 serving as a starter to start the engine 2 and to the ISG 20. The second energy storage device 31 supplies energy to at least the general load 37 and the protected load 38.

The second energy storage device 31 is connected to both the general load 37 and the protected load 38 so that the energy storage device can supply them with energy, and the switches 40 and 41 are controlled by the low voltage BMS 15 so that energy is preferably supplied to the protected load 38, constantly requiring a stable power supply.

Taking into account a state of charge (remaining charge) of the first energy storage device 30 and the second energy storage device 31 and of an operating request with regard to the general charge 37 and the protected load 38, the low voltage BMS 15 can control the switches 40 and 41 in a manner different from that of the example described above by prioritizing stable operation of the protected load 38.

In addition to the third energy storage device 33, the high voltage power supply 34 includes an inverter 45, the INVCM 14 and the high voltage BMS 16. The high voltage power supply 34 is connected to the converter unit 4 via the high voltage cable 35, so that the high voltage power supply can supply it with energy.

The inverter 45 converts / reverses an alternating current (AC) applied to the high voltage cable 35 into a direct current (DC) applied to the third energy storage device 33 and vice versa, under the control of the INVCM 14. For example, at the supply stage of the converter group 4, the INVCM 14 converts a DC supply discharged by the third energy storage device 33 into an AC supply using the inverter 45 and supplies the energy converted to converter group 4.

At the stage of regeneration of the converter group 4, the INVCM 14 reverses the AC supply generated by the converter group 4 into DC supply using the inverter 45 and charges the third energy storage device 33 with l reverse energy.

Each of the HCU 10, the ECM 11, the TCM 12, the ISGCM 13, the INVCM 14, the low voltage BMS 15, the high voltage BMS 16, and the organ ACC 17 includes a computer unit comprising a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), a flash memory which stores backup data, inter alia, an input port and a port of exit.

A program to bring the computer unit to operate within each of the HCU 10, the ECM 11, the TCM 12, the ISGCM 13, the INVCM 14, the low voltage BMS 15 , the high-voltage BMS 16, and the control unit ACC 17, as well as various constants and various cards, among others, are stored in the ROM of the computer unit.

When the CPU executes the program stored in the ROM using the RAM as a work area, the computer unit operates within each of the HCU 10, the ECM 11, the TCM 12, the ISGCM 13, INVCM 14, low voltage BMS 15, high voltage BMS 16, and control unit ACC 17 in this embodiment.

In this embodiment, the ECM 11 performs an idle stop command. In the idle stop command, the ECM 11 stops the engine 2 when a predetermined stop condition is fulfilled, and drives the ISG 20 via the ISGCM 13 to restart the engine 2 when a predetermined restart condition is fulfilled. This is why unnecessary operation of the engine 2 at idle is not carried out and the fuel consumption of the hybrid vehicle 1 can be improved.

The hybrid vehicle 1 comprises a first mode of movement in which a speed change command is carried out automatically independently of an operation by the occupant, and a second mode of travel in which a speed change command is carried out as a function of an operation by the occupant as a mode of movement of the hybrid vehicle 1.

Examples of "the operation by the occupant" are in particular an operation of an accelerator pedal or a brake pedal (which is referred to below as "operation of pedal ”) by the occupant, an operation of a gearshift switching device such as a gear lever or paddle shifters (referred to below as a shift operation speed) by the occupant, among others. The speed change control refers to the control of the actuators 51 and 52 to switch a variable speed level in the transmission mechanism 25 and to disengage and engage the clutch 26.

The first mode of movement is an automatic mode of movement in which a speed change command and a drive command are performed automatically and independently of the operation by the occupant in order to automatically effect an acceleration movement / deceleration. "Drive control" refers to the control of at least one of the motor 2 and the electric motor 4 so as to obtain a driving force necessary for the hybrid vehicle 1.

In the present embodiment, an adaptive cruise control (ACC) for automatically causing a vehicle to follow a preceding vehicle independently of a pedal operation by the occupant can be executed as an automatic movement mode.

For example, the ACC is activated by engaging a cruise control switch provided near a driver's seat of the hybrid vehicle 1.

An obstacle detector 17a is connected to the control unit ACC 17. For example, a detector capable of detecting an obstacle or a preceding vehicle which is in front of the vehicle using a millimeter wave radar, a laser radar, infrared radar, camera, among others, can be used as an obstacle detector 17a.

ACC 17 can control a distance to a previous vehicle based on information detected from the obstacle detector 17a. The control unit ACC 17 performs a gear change command and a drive command via the ECM 11 and the TCM 12 to cause the hybrid vehicle 1 to follow the preceding vehicle and to move while now a constant distance from the previous vehicle.

Control network communication lines (CAN) 48 and 49 to constitute a local area network (LAN) within the vehicle conforming to a standard, such as CAN, among others, are provided in the hybrid vehicle 1.

The HCU 10 is connected to the INVCM 14 and to the high voltage BMS 16 by the CAN 48 communication line. The HCU 10, the INVCM 14 and the high voltage BMS 16 transmit and receive a signal mutually, as a control signal, via CAN communication line 48.

The HCU 10 is connected to the ECM 11, to the TCM 12, to the ISGCM 13, to the low voltage BMS 15 and to the control unit ACC 17 by the CAN 49 communication line. The HCU 10 , the ECM 11, the TCM 12, the ISGCM 13, the low voltage BMS 15 and the control unit ACC 17 transmit and receive each other a signal, such as a control signal, via the line of CAN 49 communication.

A wheel speed detector 10a, which detects a wheel speed of each of the wheels, including the driving wheel 5, an accelerator opening degree detector 10b which detects an amount of operation of a accelerator pedal (not shown) as a throttle opening degree, a clutch stroke sensor 10c which detects a degree of clutch engagement 26, and a crankshaft angle sensor lOd are connected to the HCU 10. The HCU 10 calculates an engine speed corresponding to a engine speed 2 on the basis of information detected from the crankshaft angle detector 10d.

The wheel speed sensor 10a outputs a pulse signal to generate a pulse each time the wheel turns a predetermined angle, as a vehicle speed pulse. The HCU 10 calculates a vehicle speed of the hybrid vehicle 1 based on the vehicle speed pulse. The HCU 10 is included in a vehicle speed sensor of the present invention.

The HCU 10 performs an assist torque output command to deliver an assist torque from the electric motor 4 to the drive wheel 5 while the clutch 26 is disengaged at the time of a gear change. . The expression “while the clutch 26 is disengaged” refers to a period during which a full engagement of the clutch 26 is released (reference is made hereafter to this period as “period of incomplete engagement ”), and a half clutch condition is included in the incomplete engagement period. The half-clutch state refers to a state in which clutch friction material 26 engages with each other in a sliding state to transmit motive force.

In a vehicle provided with a clutch in a power transmission path between a transmission mechanism and a motor, a torque of the motor is not transmitted to a drive wheel during the period of incomplete engagement of the clutch at the gear change stage. Thus, the feeling of acceleration / deceleration is lost (there is what is called a lack of torque), and this lack of torque causes the sensation of idling.

The assistance torque output control prevents the sensation of idling from occurring due to a lack of torque, by delivering an assistance torque to the drive wheel 5 from the electric motor. 4 during the period of incomplete engagement of the clutch at the gear change stage.

In addition, in the present embodiment, the assistance torque output in the assistance torque output control is set to a different magnitude between the ACC and the non-ACC in which the ACC is not performed. In this embodiment, ACC is the first mode of travel, and non-ACC is the second mode of travel.

Consequently, the HCU 10 controls the electric motor 4 to deliver assistance torques having different magnitudes between the first mode of travel and the second mode of travel. More specifically, in the case of the first mode of travel, the HCU 10 controls the electric motor 4 to deliver a torque assistance whose value is less than that in the case of the second mode of travel.

In the present embodiment, an assistance torque output in the first displacement mode (during the ACC) is defined as a first assistance torque Tl, and a torque output of assistance in the second travel mode (during non-ACC) is defined as a second assistance couple T2. For example, a ratio of the first assisting torque T1 to the second assisting torque T2 is set to a predetermined ratio, such as "second assisting torque T2 x 60%". In the present embodiment, the second assistance torque T2 can be delivered in the first movement mode (during ACC) as a function of the remaining battery capacity of the third energy storage device 33.

The second assistance torque T2 is calculated by the HCU 10 on the basis of a necessary driving force calculated from a vehicle speed and a degree of accelerator opening, a degree engagement of the clutch 26, an engine rotation speed, and an engine torque indicating a torque output by the engine 2.

Here, in a flow at the speed change stage, after the complete engagement of the clutch 26 is released, the clutch 26 is completely disengaged through the clutch state at half, then a level variable speed in the transmission mechanism 25 is switched. When switching of the variable speed level ends, the clutch 26 is fully engaged through the half clutch state.

In the half clutch state, the torque from the engine 2 is transmitted to the drive wheels 50 according to a degree of engagement of the clutch 26. This is why the torque assistance at the gear change stage is gradually increased or reduced as a function of the change in the degree of engagement of the clutch 26 in the clutch state to half.

The assist torque output command carried out by the HCU 10 will be described below with reference to FIG. 2. The assist torque output command illustrated in FIG. 2 is executed repeatedly at predetermined time intervals during the period of incomplete engagement of the clutch 26.

As illustrated in Figure 2, the HCU 10 determines whether a travel mode is the first travel mode, that is to say if the ACC is running (step SI).

When it is determined in step SI that the mode of movement is not the first mode of movement, that is to say that the mode of movement is the second mode of movement (during the non -ACC), the HCU 10 controls the electric motor 4 to deliver the second assistance torque T2 as an assistance torque at the speed change stage (step S4) and terminates the assistance torque output command.

When it is determined in step SI that the mode of movement is the first mode of movement, that is to say that the ACC is running, the HCU 10 determines whether a capacity remaining battery of the third energy storage device 33 is less than a predetermined value a (step S2). The predetermined value a is set to a value at which the remaining battery capacity of the third energy storage device 33 does not immediately decrease to a value that does not allow an output of assist torque even when the second torque d T2 assistance is issued.

When it is determined in step S2 that the remaining battery capacity of the third energy storage device 33 is less than the predetermined value, the HCU 10 controls the electric motor 4 to deliver the first torque d assistance Tl as assistance torque at the speed change stage (step S3) and terminates the assistance torque output command.

When it is determined in step S2 that the remaining battery capacity of the third energy storage device 33 is not less than the predetermined value, that is to say that it is greater than or equal to the predetermined value, the HCU 10 controls the electric motor 4 to deliver the second assistance torque T2 as an assistance torque at the speed change stage (step S4) and ends the output control of assistance couple.

As has been described above, in a case in which the remaining battery charge is greater than or equal to the predetermined value, the charging power of the third energy storage device 33 is sufficient even when the second T2 assistance couple is delivered. Thus, even in the first mode of movement, the second assistance torque T2 is delivered so as not to generate the sensation of idling at the speed change stage. Therefore, in the assist torque output command illustrated in Fig. 2, the second assist torque T2 is delivered until the remaining battery capacity becomes less than the predetermined value.

FIG. 3 is a time graph for the description of an operation of the hybrid vehicle 1 in which an assistance torque output command is carried out. The time graph illustrated in FIG. 3 constitutes an example in which the remaining battery capacity becomes beforehand less than the value a predetermined at the stage tO.

In FIG. 3, as regards a necessary assistance torque, an output assistance torque, a remaining battery capacity and a vehicle driving force, a solid line indicates each value in the first mode of displacement, and a dotted line indicates each value in the second displacement mode. The assistance torque required is an assistance torque calculated by the HCU 10 on the basis of a necessary driving force, a degree of engagement of the clutch 26, an engine rotation speed and d 'a motor torque. The example illustrated in FIG. 3 represents an example in which a assistance torque calculated for each of a plurality of speed change requests is identical in the first travel mode and in the second travel mode.

The "output assistance torque" is an assistance torque actually delivered from the electric motor 4 when the electric motor 4 is controlled to deliver a necessary assistance torque calculated by the HCU 10.

Second mode of movement

As illustrated in FIG. 3, in the second mode of movement, an upper limit of assistance torque required in a case in which a gear change requirement is activated corresponds to the second assistance torque T2. When the electric motor 4 is ordered to deliver the second assistance torque T2, the remaining battery capacity does not decrease much at the stage of the first speed change request close to the time t0. Thus, an assistance torque actually delivered from the electric motor 4 becomes substantially identical to the assistance torque T2. This is why at the stage of the first gear change request, a reduction in the driving force of the vehicle rarely occurs.

Then, in the second mode of movement, even if the upper limit of the required assistance torque does not change since the second assistance couple T2 as the number of requests for change of increase increases speed, the remaining battery capacity decreases. Thus, the assistance torque actually delivered from the electric motor 4 gradually decreases. In this way, the driving force of the vehicle at the gearshift stage gradually decreases as the number of gearshift requests increases.

Therefore, in the second mode of travel, when a gear change is made several times during a predetermined period as shown in Figure 3, the occupant of the hybrid vehicle 1 gradually feels a failure of torque at the speed change stage as the number of speed change executions increases.

First mode of movement

In contrast, in the first mode of movement, an upper limit of required assistance torque, in a case in which a speed change request is activated, is limited to the first assistance torque T1 less than the second assistance torque T2.

This is why, even when the electric motor 4 is controlled to deliver the first assistance torque Tl, a degree of reduction in the remaining battery capacity is less than that in the second mode of movement. Consequently, even at the stage of a second speed change request or of a subsequent speed change request, a assistance torque actually delivered from the electric motor 4 becomes substantially identical to the assistance torque Tl.

Consequently, in the first mode of movement, even when the number of speed change requests increases, an assistance torque actually delivered from the electric motor 4 does not decrease, and thus a driving force of the vehicle at the stage of the gear change simply decreases by a certain amount. In the first mode of movement, since the upper limit of the required assistance torque, in a case in which the speed change request is activated, is limited to the first assistance torque T1 less than the second assistance torque T2, a vehicle driving force at the speed change stage decreases compared to the second mode of travel. However, when the number of speed change requests increases, and thus the remaining battery capacity decreases, a vehicle driving force in the second travel mode is less than a vehicle driving force in the first travel mode.

As described above, in the first mode of travel, when a gear change is made several times during the predetermined period, as illustrated in Figure 3, the occupant of the vehicle Hybrid 1 does not feel a displacement in which a lack of torque increases as the number of speed change executions increases.

As described above, the hybrid vehicle 1 according to the present embodiment performs an assistance torque output command to vary a quantity of an assistance torque delivered from the electric motor 4 to the drive wheel 5 during the period of incomplete engagement of the clutch 26 at the speed change stage, depending on whether the mode of travel of the hybrid vehicle 1 is the first mode of travel or the second mode of travel.

Specifically, when the travel mode is the first travel mode, the hybrid vehicle 1 according to the present embodiment controls the electric motor 4 so that a value of the assistance torque becomes lower than that in the case of the second mode of travel.

In this way, in the first mode of movement, a vehicle driving force at the speed change stage decreases compared to that in the second mode of movement. Thus, even if the occupant slightly feels the sensation of idling, it is possible to eliminate the energy consumption of the third energy storage device 33 by comparison with the second mode of movement.

Furthermore, in the second mode of movement, it is possible to deliver an assistance torque which does not cause a lack of torque at the speed change stage until the remaining battery capacity of the third device energy storage 33 decreases. In this way, in the second mode of movement, it is possible to avoid feeling the sensation of idling because of a lack of torque.

As described above, the hybrid vehicle 1 according to the present embodiment can eliminate the sensation of idling in the period of incomplete engagement of the clutch 26 at the speed change stage according to the intent of the occupier.

In addition, when the remaining battery capacity of the third energy storage device 33 is less than the predetermined value, the hybrid vehicle 1 according to the present embodiment controls the motor 4 to deliver an assistance torque. different during the period of incomplete engagement of the clutch 26 between the first mode of travel and the second mode of travel.

The HCU 10 can thus determine whether it is necessary to deliver the first assistance torque T1 less than the second assistance torque T2 at which the sensation of idling at the speed change stage can be avoided, as a couple assistance at the speed change stage, as a function of the remaining battery capacity of the third energy storage device 33.

For example, in a case where the remaining battery capacity is greater than or equal to a predetermined value, the remaining battery capacity does not immediately decrease to a value which does not allow a delivery torque to be delivered, even once the second assistance torque T2 is delivered, and thus the second assistance torque T2 is delivered with the priority of avoiding the sensation of idling operation due to a lack of torque.

Furthermore, in a case where the remaining battery capacity is less than the predetermined value, when the second assistance torque T2 is delivered, the remaining battery capacity decreases to a value which does not allow delivery an assistance torque in the case of a continuous gear change, and there is a risk that an assistance torque cannot ultimately be delivered. In this case, a great lack of torque occurs at the gear change stage. This is why, in a case where the remaining battery capacity is less than the predetermined value a, the first assistance torque T1 less than the second assistance torque T2 is delivered stably so that the capacity of remaining battery does not decrease to the value which does not allow the delivery of an assistance torque.

Second embodiment

A hybrid vehicle according to a second embodiment will be described below with reference to FIG. 4. This embodiment is different from the first embodiment in that a value of the first assistance torque is variable. However, the other configurations are identical to those of the first embodiment.

FIG. 4 is an assistance torque adjustment card in which a ratio of the first assistance torque T1 to the second assistance torque T2 is variable as a function of the vehicle speed.

In FIG. 4, a solid line indicates the first assistance torque T1, a dotted line indicates the second assistance torque T2, and an alternating long dash and short dash line indicates the ratio (in percentage ) of the first assistance torque Tl on the second assistance couple

T2.

As illustrated in FIG. 4, in the present embodiment, the second assistance torque T2 does not change as a function of the vehicle speed, and the first assistance torque Tl is adjusted to change depending on the vehicle speed when a predetermined vehicle speed is exceeded. More specifically, in the adjustment card of FIG. 4, when the predetermined vehicle speed is exceeded, the ratio of the first assistance torque T1 to the second assistance torque T2 is adjusted to decrease as the increase in vehicle speed.

Consequently, according to the adjustment card of FIG. 4, the HCU 10 controls the electric motor 4 so that the ratio of the first assistance torque T1 to the second assistance couple T2 decreases progressively increase in vehicle speed.

Since the torque that can be delivered by the electric motor 4 is a value obtained by dividing a power that can be delivered by the electric motor 4 by the vehicle speed, the torque that can be delivered by the electric motor 4 decreases as and as the vehicle speed increases. In this way, when the vehicle speed increases, the electric motor 4 cannot deliver a large assistance torque. This is why, even when the energy consumption of the third energy storage device 33 is eliminated by reducing the first assistance torque Tl as the vehicle speed increases, a vehicle driving force of hybrid vehicle 1 is less affected, which is a feature.

In the present embodiment, in a high speed vehicle region where the torque output decreases, the first assistance torque Tl is further reduced compared to a low vehicle speed region using the feature described above. It is thus possible to more effectively remove the energy consumption of the third energy storage device 33 while removing an influence on the driving force of the vehicle.

Third embodiment

A hybrid vehicle according to a third embodiment will be described below with reference to FIG. 5. This embodiment is different from the first embodiment in that a value of assistance torque increases in the case of a first mode of displacement in comparison with a case of a second mode of displacement. However, the other configurations are identical to those in the first embodiment.

In the present embodiment, when a mode of movement of the hybrid vehicle 1 is a first mode of movement, the HCU 10 controls the electric motor 4 so that the value of the assistance torque is greater than that in the case of the second mode of travel.

More specifically, for example, a ratio of a second assistance couple T2 to a first assistance couple Tl is set to a predetermined ratio, such as "first assistance couple Tl x 60%". The assistance torque calculated by the HCU 10 on the basis of a necessary driving force, a degree of engagement of the clutch 26, an engine rotation speed and an engine torque is adjusted to the first assistance torque Tl. The value obtained by multiplying the first assistance couple Tl by the predetermined ratio is adjusted to the second assistance couple T2. In the present embodiment, the first assistance torque Tl can be delivered in the second mode of movement (during the non-ACC) as a function of the remaining battery capacity of the third energy storage device 33.

An assist torque output command performed by the HCU 10 will be described below with reference to FIG. 5. The assist torque output command illustrated in FIG. 5 is executed repeatedly at predetermined time intervals during the period of incomplete engagement of the clutch 26.

As illustrated in FIG. 5, the HCU 10 determines whether a displacement mode is the second displacement mode, that is to say if the nonACC is being executed (step S21).

When it is determined, in step S21, that the displacement mode is not the second displacement mode, that is to say that the displacement mode is the first displacement mode (during ACC), the HCU 10 controls the electric motor 4 to deliver the first assistance torque Tl as an assistance torque at the speed change stage (step S24) and terminates the assistance torque output command .

When it is determined, in step 21, that the displacement mode is the second displacement mode, that is to say that the non-ACC is being executed, the HCU 10 determines if a remaining battery capacity of the third energy storage device 33 is less than a predetermined value a (step S22).

When it is determined, in step S22, that the remaining battery capacity of the third energy storage device 33 is less than the predetermined value, the HCU 10 controls the electric motor 4 to deliver the second assist torque T2 as assist torque at the speed change stage (step S23) and terminate the assist torque output command.

When it is determined, in step S22, that the remaining battery capacity of the third energy storage device 33 is not less than the predetermined value a, that is to say that it is greater than or equal to the predetermined value, the HCU 10 controls the electric motor 4 to deliver the first assistance torque T1 as an assistance torque at the speed change stage (step S24) and ends the control of assistance torque output.

As described above, in a case in which the remaining battery charge is greater than or equal to the predetermined value, a charging power of the third energy storage device 33 is sufficient even when the first assistance couple Tl is delivered. Thus, even in the second mode of movement, the first assistance torque Tl is delivered so as not to give the sensation of operating at idle at the speed change stage. Therefore, in the assist torque output command illustrated in Figure 5, the first assist torque Tl is delivered until the remaining battery capacity becomes less than the predetermined value.

[YES] Figure 6 is a time graph for describing the operation of the hybrid vehicle 1 in which an assist torque output command is performed. The time graph illustrated in FIG. 6 constitutes an example in which the remaining battery capacity becomes beforehand less than the value a predetermined at time t0.

In FIG. 6, the respective values of a necessary assistance torque, an output assistance torque, a remaining battery capacity and a vehicle driving force, are indicated by a solid line in the second mode. of displacement, and by a dotted line in the first mode of displacement. The example illustrated in FIG. 6 represents a case in which a torque of necessary assistance calculated for each of a plurality of speed change requests is identical in the first mode of travel and in the second mode of travel.

First mode of movement

As illustrated in FIG. 6, in the first mode of movement, an upper limit of the assistance torque required in a case where a speed change request is activated corresponds to the first assistance torque Tl. When the electric motor 4 is controlled to deliver the first assistance torque Tl, the remaining battery capacity does not decrease much at the stage of the first speed change request close to the time tO. Thus, an assistance torque actually delivered from the electric motor 4 becomes substantially identical to the assistance torque Tl. This is why, at the stage of the first speed change request, a reduction in the driving force of the vehicle occurs only rarely.

Then, in the first mode of movement, even if the upper limit of the required assistance torque does not change compared to the first assistance torque Tl as the number of change requests increases speed, the remaining battery capacity decreases. Thus, the assistance torque actually delivered by the electric motor 4 gradually decreases. In this way, the driving force of the vehicle at the gearshift stage gradually decreases as the number of gearshift requests increases.

Consequently, in the first mode of movement, when a speed change is made several times during a predetermined period as illustrated in FIG. 6, the occupant of the hybrid vehicle 1 progressively feels a failure of torque at the speed change stage as the number of speed change executions increases.

Second mode of movement

In contrast, in the second travel mode, an upper limit of required assistance torque, in a case in which a gear change request is activated, is limited to the second assistance torque T2 lower than the first assistance torque Tl.

This is why, even when the electric motor 4 is controlled to deliver the second assistance torque T2, a degree of reduction in the remaining battery capacity is less than that in the first mode of movement. Consequently, even at the stage of a second speed change request or of a subsequent speed change request, an assistance torque actually delivered from the electric motor 4 becomes substantially identical to the assistance torque T2.

Consequently, in the second mode of movement, even when the number of speed change inquiries increases, an assistance torque actually delivered from the electric motor 4 does not decrease, and thus a driving force of the vehicle at the stage of shifting simply decreases by a certain amount. In the second mode of movement, since the upper limit of the necessary assistance torque is limited to the second assistance torque T2 lower than the first assistance torque Tl, in a case where the speed change request is activated, a force driving vehicle at the gear change stage decreases in comparison with the first mode of travel. However, when the number of speed change requests increases, and thus the remaining battery capacity decreases, a vehicle driving force in the first travel mode is less than a vehicle driving force in the second travel mode.

As described above, in the second mode of travel, when a gear change is made several times during the predetermined period, as illustrated in Figure 6, the occupant of the vehicle Hybrid 1 does not feel a displacement in which a lack of torque increases as the number of speed change executions increases.

As described above, the hybrid vehicle 1 according to the present embodiment performs an assistance torque output command to vary a quantity of an assistance torque delivered from the electric motor 4 to the drive wheel 5 during the period of incomplete engagement of the clutch 26 at the speed change stage, depending on whether the mode of travel of the hybrid vehicle 1 is the first mode of travel or the second mode of travel.

Specifically, when the mode of travel is the first mode of travel, the hybrid vehicle 1 according to the present embodiment controls the electric motor 4 so that a value of the assistance torque becomes greater than that in the case of the second mode of travel.

In this way, in the second mode of movement, a driving force of the vehicle at the speed change stage decreases compared to that in the first mode of movement. Thus, even if the occupant slightly feels the sensation of idling, it is possible to eliminate the energy consumption of the third energy storage device 33 by comparison with the first mode of movement.

Furthermore, in the first mode of movement, it is possible to deliver an assistance torque which does not cause a lack of torque at the speed change stage until the reduction of the remaining battery capacity of the third energy storage device 33. In this way, in the first mode of movement, it is possible to avoid feeling the sensation of operating at idle due to a lack of torque.

As described above, the hybrid vehicle 1 according to the present embodiment can eliminate the sensation of idling in the period of incomplete engagement of the clutch 26 at the speed change stage according to the intent of the occupier.

In addition, when the remaining battery capacity of the third energy storage device 33 is less than the predetermined value, the hybrid vehicle 1 according to this embodiment controls the motor 4 to deliver assistance torque different in the period of incomplete engagement of the clutch 26 between the first mode of travel and the second mode of travel.

The HCU 10 can thus determine whether it is necessary to deliver the second assistance torque T2 lower than the first assistance torque Tl to which the sensation of idling at the speed change stage can be avoided, as a torque assistance at the speed change stage as a function of the remaining battery capacity of the third energy storage device 33.

For example, in a case in which the remaining battery capacity is greater than or equal to the predetermined value a, the remaining battery capacity does not immediately decrease to a value which does not allow a delivery torque to be delivered even when the first assistance torque Tl is delivered, and thus the first assistance torque Tl is delivered while prioritizing avoiding the sensation of idling operation due to a lack of torque.

Furthermore, in a case in which the remaining battery capacity is less than the predetermined value, when the first assistance torque Tl is delivered, the remaining battery capacity decreases to a value which does not allow deliver an assist torque in a case where a gear change is continuous, and there is a risk that an assist torque may not be delivered in the end. In this case, a great lack of torque occurs at the gear change stage. This is why, in a case in which the remaining battery capacity is less than the predetermined value a, the second assistance torque T2 less than the first assistance torque Tl is delivered stably so that the capacity of remaining battery does not decrease to the value which does not allow the delivery of an assistance torque.

Fourth embodiment

A hybrid vehicle according to a fourth embodiment will be described below with reference to FIG. 7. This embodiment is different from the third embodiment in that a value of the second assistance torque is variable. However, the other configurations are identical to those of the first embodiment and the third embodiment.

FIG. 7 is an assistance torque adjustment card in which a ratio of the second assistance torque T2 to the first assistance torque Tl is variable as a function of the vehicle speed.

In FIG. 7, a dotted line indicates the first assistance torque T1, a solid line indicates the second assistance torque T2, and an alternating long dash and short dash line indicates the ratio (in percentage ) of the second assistance torque T2 on the first assistance torque Tl.

As illustrated in FIG. 7, in the present embodiment, the first assistance torque T1 does not change as a function of the vehicle speed, and the second assistance torque T2 is adjusted to change depending on the vehicle speed when a predetermined vehicle speed is exceeded. More specifically, in the adjustment card of FIG. 7, when the predetermined vehicle speed is exceeded, the ratio of the second assistance torque T2 to the first assistance torque Tl is adjusted to decrease as the increase in vehicle speed.

Consequently, according to the adjustment card of FIG. 7, the HCU 10 controls the electric motor 4 so that the ratio of the second assistance torque T2 to the first assistance torque T1 decreases progressively increase in vehicle speed.

Since a torque that can be delivered by the electric motor 4 is a value obtained by dividing a power that can be delivered by the electric motor 4 by the vehicle speed, the torque that can be delivered by the electric motor 4 decreases as and as the vehicle speed increases. In this way, when the vehicle speed increases, the electric motor 4 cannot deliver a large assistance torque. This is why, even when an energy consumption of the third energy storage device 33 is eliminated by reducing the second assistance torque T2 as the vehicle speed increases, a vehicle driving force of the hybrid vehicle 1 is less affected, which is a characteristic.

In the present embodiment, in a region of high vehicle speed in which a torque output decreases, the second assistance torque T2 is reduced further compared to a region of low vehicle speed using the characteristic described above. It is thus possible to more effectively remove the energy consumption of the third energy storage device 33 while removing an influence on the driving force of the vehicle.

In each of the embodiments described above, a description of an example in which the first mode of movement is an automatic movement mode has been presented. However, the present invention is not limited to this. For example, the first mode of movement can be a manual mode. Manual mode is a mode in which a speed change command is made in response to an occupant speed change operation.

[0137] In addition, in each of the embodiments described above, a description of an example in which the ACC can be executed as an automatic displacement mode has been presented. However, the present invention is not limited to this. For example, cruise control can be performed as an automatic travel mode. The cruise control corresponds to a constant speed movement command which causes the vehicle to move at a constant speed without any pedal operation by the occupant.

In addition, in each of the embodiments described above, the HCU 10 controls the torque delivered by the electric motor 4 in the assistance torque output control at the speed change stage as torque d 'assistance. However, the present invention is not limited to this. The power of the electric motor 4 can be controlled as an assistance power in the assistance torque output control at the speed change stage.

[0139] Although embodiments of the present invention have been described, those skilled in the art can realize that changes can be made without departing from the scope of the present invention. All such modifications and their equivalents fall within the scope of the appended claims.

Claims (7)

1. Hybrid vehicle (1) characterized in that it comprises: a combustion engine (2) and an electric motor (4) serving as a drive source transmitting power to a drive wheel (5); an automatic transmission (3) for adapting a rotation to the output of the engine (2) and transmitting it to the drive wheel (5), the automatic transmission (3) comprising a clutch (26) disengaging or engaging a power transmission path between the automatic transmission (3) and the engine (2); and a control member (10) for controlling an assistance torque delivered by the electric motor (4) in an incomplete engagement period of the clutch (26) according to a mode of movement of the hybrid vehicle (1) is a first mode of travel or a second mode of travel, a speed change command being automatically performed independently of an operation by an occupant in the first mode of travel, a speed change command being performed based on a occupant operation in the second mode of travel. 2. Hybrid vehicle (1) according to claim 1, characterized in that the first displacement mode is an automatic displacement mode in which a speed change command and a drive command are performed automatically independently of the operation by the occupant to automatically perform an acceleration / deceleration movement. 3. Hybrid vehicle (1) according to one of claims 1 or 2, characterized in that, in a case in which the mode of movement is the first mode of movement, the control member (10) performs a control operation of so that a value of the assistance torque is less than a corresponding value in a case in which the mode of movement is the second mode of movement. 4. Hybrid vehicle (1) according to claim 3, characterized in that it further comprises: a vehicle speed sensor (10a) for detecting a vehicle speed of the hybrid vehicle (1), wherein, when the assist torque of a case where the travel mode is the first travel mode is defined as as the first assistance torque, and the assistance torque of a case where the displacement mode is the second displacement mode is defined as the second assistance torque, the control member (10) performs an operation so that a ratio of the first assist torque to the second assist torque decreases as the vehicle speed increases detected by the vehicle speed sensor (10a). 5. Hybrid vehicle (1) according to one of claims 1 or 2, characterized in that, when the mode of movement is the first mode of movement, the control member (10) performs a control operation so that a value of the assistance torque is greater than a corresponding value in a case where the mode of movement is the second mode of movement. 6. Hybrid vehicle (1) according to claim 3, characterized in that it further comprises: a vehicle speed sensor (10a) for detecting a vehicle speed of the hybrid vehicle (1), wherein, when the assist torque of a case where the travel mode is the first travel mode is defined as as the first assistance torque, and the assistance torque of a case where the displacement mode is the second displacement mode is defined as the second assistance torque, the control member (10) performs an operation so that a ratio of the second assist torque to the first assist torque decreases as the vehicle speed increases detected by the vehicle speed sensor (10a). 7. Hybrid vehicle (1) according to any one of claims 1 to 6, characterized in that it further comprises: a battery (33) for supplying energy to the electric motor (4), wherein, when a remaining capacity of the battery (33) is less than a predetermined value, the controller (10) performs an operation control so that the electric motor (4) delivers a different assistance torque in the period of incomplete engagement of the clutch (26) between the first mode of 5 displacement and the second mode of displacement. 1/7 CD LL · 2/7