JP2023034321A - hybrid vehicle - Google Patents

Abstract

To provide a hybrid vehicle in which restart of a control device during travelling is easy to be recognized by a driver.SOLUTION: (a) An electronic control device 100 controls travelling drive force transmitted from a travelling drive force source PG to a driving wheel 14. (b) The electronic control device 100 executes control for stopping an engine 12 when predetermined conditions including a neutral state of an automatic transmission 28 are established. (c) The electronic control device 100 which is restarted during travelling starts the engine 12 when the automatic transmission 28 is in the neutral state and continues operation of the started engine 12 although the predetermined conditions are established when the neutral state of the automatic transmission 28 continues.SELECTED DRAWING: Figure 1

Description

The present invention relates to an internal combustion engine and an electric motor that are driving force sources for running, a power transmission device provided in a power transmission path between the driving force source for running and drive wheels, and the driving force sources for running and power transmission. and a control device for controlling the device.

It controls an internal combustion engine and an electric motor as driving force sources for traveling, a power transmission device provided in a power transmission path between the driving force source for traveling and the drive wheels, and the driving force source and power transmission device for traveling. A hybrid vehicle comprising a control device is known. For example, the one described in Patent Document 1 is it. In the hybrid vehicle described in Patent Document 1, the control device that is restarted during running can start the driving force source (internal combustion engine and electric motor) for running while the power transmission device is in the neutral state before the running stops. Are listed. The driver can easily recognize that the control device has been restarted by starting the internal combustion engine, which is the driving force source for running.

JP 2013-139223 A

By the way, in order to suppress the fuel consumption in the internal combustion engine, for example, during coasting (coast running in which the power transmission device is in the neutral state) when the accelerator pedal is not depressed, fuel is controlled to stop the supply of fuel to the internal combustion engine. It has cut control. In the hybrid vehicle described in Patent Document 1, when fuel cut control is adopted, the control device that is restarted during running starts the internal combustion engine that is the driving force source for running while the power transmission device is in the neutral state. Despite this, there is a risk that the internal combustion engine will be stopped immediately by the fuel cut control. If the internal combustion engine is stopped immediately after being started in this manner, the driver may not recognize that the control device has been restarted.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a hybrid vehicle in which the driver can easily recognize that the control device has been restarted while the vehicle is running.

The gist of the present invention is to provide an internal combustion engine and an electric motor as driving force sources for running, a power transmission device provided in a power transmission path between the driving force source for running and driving wheels, and the driving power source. A hybrid vehicle comprising: a drive force source and a control device that controls the power transmission device, wherein: (a) the control device controls travel drive force transmitted from the travel drive force source to the drive wheels; (b) the control device executes control to stop the internal combustion engine when a predetermined condition including that the power transmission device is in a neutral state is satisfied; The restarted control device starts the internal combustion engine with the power transmission device in a neutral state, and even if the predetermined condition is satisfied when the power transmission device continues to be in the neutral state. To continue the operation of the internal combustion engine that has been started.

According to the hybrid vehicle of the present invention, (a) the control device controls the running driving force transmitted from the running driving force source to the driving wheels; When a predetermined condition including that the device is in a neutral state is established, control is executed to stop the internal combustion engine; The internal combustion engine is started in a neutral state, and the operation of the started internal combustion engine is continued even if the predetermined condition is satisfied when the power transmission device continues to be in the neutral state. In this way, the control device that has been restarted during running starts the internal combustion engine when the power transmission device is in the neutral state, and stops the internal combustion engine when the power transmission device continues to be in the neutral state. To continue the operation of the started internal combustion engine even if the condition of (1) is established. As a result, when the neutral state of the power transmission device continues, the started internal combustion engine is not immediately stopped, so that the driver can easily recognize that the control device has been restarted while the vehicle is running. Become.

1 is a schematic configuration diagram of a hybrid vehicle according to an embodiment of the present invention, and a functional block diagram showing main parts of control functions for various controls in the hybrid vehicle; FIG. FIG. 2 is an example of a flow chart for explaining the control operation of the electronic control unit shown in FIG. 1; FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following examples, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, etc. of each part are not necessarily drawn accurately.

FIG. 1 is a schematic configuration diagram of a hybrid vehicle 10 (hereinafter simply referred to as "vehicle 10") according to an embodiment of the present invention, and also functions representing essential control functions for various controls in the vehicle 10. It is a block diagram.

The vehicle 10 is a hybrid vehicle that includes an engine 12, which is a driving force source PG, and an electric motor MG. A power transmission path PT is provided between the traveling driving force source PG (engine 12, electric motor MG) and the drive wheels 14 . The vehicle 10 includes an engine connecting shaft 20, a clutch K0, an electric motor connecting shaft 22, a torque converter 24, an automatic transmission 28, in this order from the engine 12 side in a power transmission path PT in a case 18, which is a non-rotating member attached to the vehicle body. , an AT input shaft 26, an automatic transmission 28, and the like, which are input rotary members. The vehicle 10 also includes a differential gear 32 connected to an AT output shaft 30, which is an output rotary member of the automatic transmission 28, a pair of drive shafts 34 connected to the differential gear 32, and the like, in the power transmission path PT. The vehicle 10 also includes an inverter 52 , a hydraulic control circuit 54 , an EOP 56 that is an electric oil pump, a battery 60 , a shift lever 90 , a power switch 94 and an electronic control unit 100 .

Engine 12 is a well-known internal combustion engine. An engine control device 50 including a throttle actuator, a fuel injection device, an ignition device, etc. provided in the vehicle 10 is controlled by an electronic control device 100, which will be described later. [Nm] is controlled. In this specification, torque, driving force, power, and power are synonymous unless they are specifically distinguished.

The engine connecting shaft 20 is a member that connects the engine 12 and the clutch K0, and is, for example, a crankshaft.

The electric motor MG is a so-called motor generator having, for example, a function as a motor that generates mechanical power from electrical energy (motor function) and a function as a generator that generates electrical energy from mechanical power (generator function). is. As used herein, motive power is synonymous with drive power, torque, and force unless otherwise distinguished. The electric motor MG is connected to a battery 60 provided in the vehicle 10 via an inverter 52 which will be described later. The battery 60 is a power storage device that transfers electric power to and from the electric motor MG. In the electric motor MG, the electric motor torque Tmg [Nm], which is the output torque of the electric motor MG, is controlled by controlling the inverter 52 by the electronic control unit 100 which will be described later. Note that the electric motor MG corresponds to the "electric motor" in the present invention.

A clutch K0 is provided between an engine connection shaft 20 connected to the engine 12 and an electric motor connection shaft 22 connected to the rotor of the electric motor MG. The clutch K0 is an engagement device capable of connecting and disconnecting power transmission between the engine 12 and the electric motor connecting shaft 22, and is, for example, a wet multi-plate hydraulic friction engagement device. When clutch K0 is engaged, clutch K0 enables power transmission between engine 12 and electric motor MG. When the clutch K0 is released, the clutch K0 disconnects power transmission between the engine 12 and the electric motor MG. When the clutch K0 is brought into a semi-engaged state, i.e., a slip-engaged state, the clutch K0 allows the transmission torque capacity (engagement force of the clutch K0) based on the slip-engaged state to increase the torque between the engine 12 and the electric motor MG. Enables power transmission.

Electric motor MG is rotationally driven by electric power stored in battery 60 and outputs driving force for running hybrid vehicle 10 . Further, the electric motor MG generates electric power using driving force for traveling input from the engine 12 via the clutch K0, or converts the driven force input from the driving wheel 14 side into electric power through regeneration. The generated electric power is charged to the battery 60 via the inverter 52 .

Inverter 52 is a power supply circuit provided between electric motor MG and battery 60 and controlled by electronic control unit 100 to convert direct current into alternating current or convert alternating current into direct current. For example, the inverter 52 converts direct current supplied from the battery 60 into alternating current and outputs it to the electric motor MG to drive it, or converts alternating current generated by the electric motor MG into direct current and outputs it to the battery 60 .

The battery 60 is, for example, a rechargeable secondary battery such as a lithium-ion battery or a nickel-metal hydride battery. The battery 60 is mainly used to supply electric power for driving the electric motor MG and to charge electric power generated by the electric motor MG through regeneration.

Torque converter 24 is a known torque converter. The torque converter 24 includes a pump impeller connected to the electric motor connecting shaft 22, a turbine impeller connected to the AT input shaft 26, and a lockup clutch 40 that directly connects the pump impeller and the turbine impeller. . The torque converter 24 is disposed on a power transmission path PT between the driving force source PG (engine 12, electric motor MG) and the drive wheels 14, and converts the driving force for driving output from the driving force source PG. It is a hydrodynamic transmission capable of transmitting power from the electric motor connecting shaft 22 to the AT input shaft 26 via fluid. Vehicle 10 includes MOP 42, which is a mechanical oil pump. The MOP 42 is connected to the pump impeller, is rotationally driven by the driving force source PG (the engine 12 and the electric motor MG), and discharges hydraulic oil OIL used in each part within the case 18 .

The EOP 56 is a well-known oil pump that can be driven by the rotation of the EOP drive motor 58 independently of the rotation of the engine 12 and the electric motor MG, which are the drive power source PG. The EOP drive motor 58 is a well-known electric motor, and the rotational speed of the EOP drive motor 58 is controlled by controlling an inverter (not shown) by the electronic control unit 100 . The EOP 56 is rotationally driven by an EOP drive motor 58 and discharges hydraulic oil OIL used in each part within the case 18 .

The automatic transmission 28 is a well-known automatic transmission that changes the speed of the driving force input to the AT input shaft 26 from the driving force source PG (the engine 12 and the electric motor MG) and outputs it to the AT output shaft 30. , for example, a planetary gear type or constant mesh type parallel shaft type stepped transmission, or a belt type or power roller type continuously variable transmission. The automatic transmission 28 has different gear ratios (also referred to as gear ratios) γat (=AT input rotational speed Ni [rpm]/AT output rotational speed No [rpm]) by a hydraulic control circuit 54 controlled by an electronic control unit 100. is controlled to form a desired gear ratio γat. In this embodiment, the automatic transmission 28 is a well-known planetary gear type automatic transmission including a plurality of sets of planetary gear devices and a plurality of transmission engagement devices CB. Each gear shift engagement device CB is fully engaged and partially engaged by regulating the hydraulic pressure supplied from the hydraulic control circuit 54 to the hydraulic actuators that control the connection/disengagement state of the gear shift engagement device CB. Connection/disconnection states such as a connected state and a released state are switched. In the automatic transmission 28, one of a plurality of gear stages (also referred to as gear stages) having different gear ratios γat is shifted by engagement of any one of the shift engagement devices CB. It is formed. Further, the automatic transmission 28 can be brought into a neutral state in which the driving force for driving output from the driving force source PG for driving is not transmitted to the driving wheels 14 . The automatic transmission 28 corresponds to the "power transmission device" in the present invention.

The differential gear 32 receives driving force for running transmitted from the AT output shaft 30 of the automatic transmission 28, and transmits equal driving torque to the pair of drive shafts 34 while allowing an appropriate rotational speed difference. It is a well-known differential gear.

The shift operation position POSsh of the shift lever 90 is, for example, each operation position of "P operation position", "R operation position", "N operation position", and "D operation position". The P operation position is a parking operation position in which the automatic transmission 28 is placed in the P range (=the range in which the AT output shaft 30 is mechanically fixed so as not to rotate). The R operation position is a reverse travel operation position in which the automatic transmission 28 is placed in the R range (=range in which the vehicle 10 can travel in reverse). The N operating position is a neutral operating position in which the automatic transmission 28 is placed in the N range (=the neutral state range). The D operating position is a forward travel operating position in which the automatic transmission 28 is placed in the D range (=a range in which forward travel is possible by executing automatic shift control using all gear stages of the automatic transmission 28). When the driver selects one of the "P operating position", "R operating position", "N operating position", and "D operating position", the shift range of the automatic transmission 28 is set to "P" (= P range), "R" (=R range), "N" (=N range), and "D" (=D range). In the shift range of the automatic transmission 28, "P" and "N" are non-driving ranges, and "R" and "D" are driving ranges.

The hydraulic control circuit 54 uses the hydraulic pressure of the hydraulic oil OIL discharged from the MOP 42 and the EOP 56 as a source pressure, and supplies necessary hydraulic oil OIL to each part in the case 18 . For example, the hydraulic control circuit 54 generates hydraulic pressure for controlling connection/disengagement of the clutch K0, hydraulic pressure for shift control of the automatic transmission 28, and hydraulic pressure for connection/disconnection control of the lockup clutch 40 of the torque converter 24. 18 to each hydraulic actuator.

When the clutch K0 is engaged, the driving force for running output from the engine 12 is transmitted from the engine connection shaft 20 to the clutch K0, the electric motor connection shaft 22, the torque converter 24, the automatic transmission 28, the differential gear 32, and the drive shaft 34, etc., to the drive wheels 14 in sequence. The driving force for running that is output from the electric motor MG is sequentially transmitted from the electric motor connecting shaft 22 through the torque converter 24, the automatic transmission 28, the differential gear 32, the drive shaft 34, and the like, regardless of whether the clutch K0 is engaged or disengaged. It is transmitted to the drive wheels 14 .

In the vehicle 10, one of the BEV driving mode, the engine driving mode, and the HEV driving mode can be selected. The BEV driving mode is a driving mode in which BEV (Battery Electric Vehicle) driving is performed using only the electric motor MG as a driving force source among the driving force sources PG for driving by controlling the power running of the electric motor MG with the engine 12 stopped. is. The engine driving mode is a driving mode in which the clutch K0 is engaged and only the engine 12 of the driving force source PG is used as the driving force source. The HEV travel mode is a travel mode in which the clutch K0 is engaged and HEV (Hybrid Electric Vehicle) travel is performed using both the engine 12 and the electric motor MG of the travel drive power source PG as the drive power sources.

Which one of the BEV driving mode, the engine driving mode, and the HEV driving mode is used for driving the vehicle 10 is switched by, for example, a driving force source switching map. The driving force source switching map is a relation in which the driving modes are predetermined in two-dimensional coordinates with variables such as the vehicle speed V [km/h] and the required driving torque Trdem [Nm]. The required drive torque Trdem is the drive torque Tr [Nm] required for the vehicle 10, and is the drive torque required for the drive wheels 14, for example. A method of calculating the required drive torque Trdem will be described later.

BEV driving mode in a low vehicle speed region where the vehicle speed V is relatively low and a low load region where the required driving torque Trdem is relatively low (=a region where the accelerator opening θacc [%] is relatively low), where engine efficiency generally decreases. is the region to be selected. On the other hand, in the high vehicle speed range where the vehicle speed V is relatively high or in the high load range where the required driving torque Trdem is relatively high (=the range where the accelerator opening θacc is relatively high), the engine running mode or the HEV running mode is selected. area. The BEV running mode is applied when the SOC [%] of the state of charge of the battery 60 (the ratio of the amount of charge actually stored to the predetermined full charge capacity) is equal to or greater than a predetermined engine start threshold. . In other words, when the state of charge value SOC of the battery 60 is less than the predetermined engine start threshold, there is no area in the driving force source switching map in which the BEV driving mode is selected, and the engine driving mode or the HEV driving mode is selected for all. It is the same as being the area to be done. In the engine running mode or the HEV running mode, the electric motor rotation speed Nmg [rpm], which is the rotation speed of the electric motor MG, is the same value as the engine rotation speed Ne [rpm], which is the rotation speed of the engine 12 . The predetermined engine start threshold is a predetermined threshold for determining the state of charge value SOC at which it is necessary to forcibly start engine 12 and charge battery 60 .

The power switch 94 is a switch for the driver to request that the electronic control unit 100, which is a system for running the vehicle 10, be switched between starting and stopping for each operation. For example, when the power switch 94 is operated (for example, long-pressed) while the vehicle is running, the electronic control unit 100 can be stopped. Further, when the power switch 94 is operated after the electronic control unit 100 has stopped during running (=restart is requested by the driver), the electronic control unit 100 is restarted. It is ready to start. When the driver operates the power switch 94 to start the electronic control unit 100 , the power switch 94 outputs a start signal ST, which is a signal requesting starting, to the electronic control unit 100 .

The electronic control unit 100 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, and an input/output interface. Various controls of the vehicle 10 are executed by performing signal processing. The electronic control unit 100 includes computers for engine control, electric motor control, hydraulic control, etc., as required. The electronic control device 100 corresponds to the "control device" in the present invention.

The electronic control unit 100 includes various sensors (for example, an engine rotation speed sensor 70, a turbine rotation speed sensor 72, an output rotation speed sensor 74, an electric motor rotation speed sensor 76, an accelerator opening sensor 78, a brake operation sensor, etc.) provided in the vehicle 10. amount sensor 80, throttle valve opening sensor 82, battery sensor 84, shift position sensor 92, power switch 94, etc.) various signals based on detected values (for example, engine rotation speed Ne [rpm], which is the rotation speed of engine 12; Turbine rotation speed Nt [rpm] which is equivalent to AT input rotation speed Ni [rpm], AT output rotation speed No [rpm] corresponding to vehicle speed V, electric motor rotation speed Nmg [rpm] which is the rotation speed of electric motor MG, operation The accelerator opening θacc [%], which is the amount of accelerator operation by the driver that indicates the magnitude of the driver's acceleration operation; the amount of brake operation θbrk [%], which indicates the magnitude of the deceleration operation by the driver; throttle valve opening θth [%], battery temperature THbat [°C] of battery 60, battery charge/discharge current Ibat [A], battery voltage Vbat [V], operation of shift lever 90 operated by the driver A shift operation position POSsh representing a position, a start signal ST which is a signal requesting activation of the electronic control unit 100 by the operation of the power switch 94 by the driver, etc.) are input respectively.

From the electronic control unit 100, various command signals (for example, for controlling the engine 12) are sent to each device (for example, the engine control unit 50, the inverter 52, the hydraulic control circuit 54, the EOP drive motor 58, etc.) provided in the vehicle 10. The engine control signal Se, the electric motor control signal Smg for controlling the electric motor MG, the shift control signal Sat for controlling the shift engaging device CB, the K0 control signal Sk0 for controlling the clutch K0, and the lockup clutch 40 are LU control signal Slu for control, EOP control signal Seop for controlling EOP 56, etc.) are respectively output.

The electronic control unit 100 functionally includes a hybrid control unit 102 , a clutch control unit 104 , a shift control unit 106 , a fuel cut determination unit 108 , a restart determination unit 110 and a start continuation determination unit 112 .

The hybrid control unit 102 functionally includes an engine control unit 102a that controls the operation of the engine 12, and an electric motor control unit 102b that controls the operation of the electric motor MG via the inverter 52. and hybrid drive control by the electric motor MG.

The hybrid control unit 102 calculates the required driving amount (for example, the required driving torque Trdem) for the vehicle 10 by the driver by applying the actual accelerator opening θacc and the vehicle speed V to the required driving amount map, for example. The required drive amount map is a map in which the relationship between the accelerator opening θacc and the vehicle speed V and the required drive amount is predetermined and stored experimentally or by design. The required drive amount is the drive amount required for the vehicle 10, and is, for example, the required drive torque Trdem. In other words, the required drive torque Trdem is the required drive power Prdem [W] at the vehicle speed V at that time. As the required driving amount, the required driving force Frdem [N] at the driving wheels 14, the required output torque at the AT output shaft 30, and the like can be used. In the calculation of the required drive amount, instead of the vehicle speed V, the AT output rotational speed No or the like may be used. Thus, the required drive torque Trdem, the required drive power Prdem, the required drive force Frdem, and the required output torque of the AT output shaft 30 are synonymous in that they are the required drive amount of the vehicle 10 .

The hybrid control unit 102 considers the transmission loss, the auxiliary load, the gear ratio γat of the automatic transmission 28, the chargeable power Win [W] and the dischargeable power Wout [W] of the battery 60, etc., and determines the required driving power Prdem , an engine control signal Se for controlling the engine 12 and an electric motor control signal Smg for controlling the electric motor MG are output. The engine control signal Se is, for example, a command value of the engine power Pe [W], which is the power of the engine 12 that outputs the engine torque Te at the engine rotation speed Ne at that time. The electric motor control signal Smg is, for example, a command value for the power consumption Wm [W] of the electric motor MG that outputs the electric motor torque Tmg at the electric motor rotation speed Nmg at that time.

The chargeable power Win of the battery 60 is the maximum power that can be input that defines the limit of the input power of the battery 60 and indicates the input limit of the battery 60 . The dischargeable power Wout of the battery 60 is the maximum power that can be output that defines the limit of the output power of the battery 60 and indicates the output limit of the battery 60 . The chargeable power Win and the dischargeable power Wout of the battery 60 are calculated by the electronic control unit 100 based on the battery temperature THbat and the state of charge value SOC of the battery 60, for example.

Hybrid control unit 102 controls vehicle 10 in a driving mode (BEV driving mode, engine driving mode, HEV driving mode) according to the state of vehicle 10 . For example, the driving mode according to the state of the vehicle 10 is selected by the driving force source switching map described above.

The engine control unit 102a controls the engine torque Te so as to achieve the required drive amount for the vehicle 10 . The electric motor control unit 102b executes torque control for controlling the electric motor torque Tmg so as to achieve the required drive amount for the vehicle 10 during running with the accelerator on. The accelerator ON state is a vehicle state in which the driver operates the accelerator (for example, the driver depresses the accelerator pedal Acc) and the accelerator opening θacc is greater than zero. The torque control is a control to bring the electric motor torque Tmg to a predetermined target torque so as to realize the required driving amount of the vehicle 10 . Specifically, in traveling in the BEV traveling mode, the electric motor control unit 102b controls the electric motor torque Tmg so as to achieve the required driving torque Trdem. In running in the engine running mode, the engine control unit 102a controls the engine torque Te so as to achieve the entire required driving torque Trdem, and the electric motor control unit 102b controls the engine torque Te with respect to the required driving torque Trdem. If there is a surplus, the motor torque Tmg is controlled so that the surplus is used to generate power. During traveling in the HEV traveling mode, the engine control unit 102a controls the engine torque Te so as to achieve a portion of the required driving torque Trdem, and the electric motor control unit 102b controls the engine torque Te with respect to the required driving torque Trdem. Then, the motor torque Tmg is controlled so as to compensate for the insufficient torque.

The hybrid control unit 102 further functionally includes a starting control unit 102c. The start control unit 102c and the clutch control unit 104 execute engine start control for starting the engine 12 by cranking the engine 12 using the electric motor MG and the clutch K0 as necessary. Specifically, in accordance with the switching of the clutch K0 from the released state to the engaged state by the clutch control unit 104, the start control unit 102c causes the electric motor MG to output the cranking torque Tcr [Nm] until the cranking ends. control to Further, the start control unit 102c controls fuel supply to the engine 12, ignition, and the like in conjunction with cranking of the engine 12 by the clutch K0 and the electric motor MG.

The shift control unit 106 determines the shift of the automatic transmission 28 using, for example, a shift map, and outputs a shift control signal Sat for executing shift control to the hydraulic control circuit 54 as necessary. The shift map is a predetermined relation having a shift line for judging the shift of the automatic transmission 28 on two-dimensional coordinates having, for example, the vehicle speed V and the required drive torque Trdem as variables. In the shift map, the AT output rotational speed No may be used instead of the vehicle speed V, and the required driving force Frdem, the accelerator opening θacc, the throttle valve opening θth, etc. may be used instead of the required driving torque Trdem. Also good.

A fuel cut determination unit 108 determines whether or not a predetermined condition for executing fuel cut control is satisfied when the engine 12 is in an operating state. For example, the predetermined condition is that the automatic transmission 28 is in a neutral state, and that the vehicle is coasting in which neither the accelerator operation nor the brake operation is performed by the driver. For example, when the accelerator opening θacc is less than the predetermined opening determination value θacc_jdg and the brake operation amount θbrk is less than the predetermined operation amount determination value θbrk_jdg, neither accelerator operation nor brake operation is performed by the driver. is determined. Note that the predetermined opening degree determination value θacc_jdg is a predetermined determination value for determining that the accelerator operation is not performed by the driver. The predetermined operation amount determination value θbrk_jdg is a predetermined determination value for determining that the driver is not performing a brake operation.

When the fuel cut determination unit 108 determines that a predetermined condition for executing fuel cut control is satisfied, the engine control unit 102a performs fuel cut control to stop the supply of fuel to the engine 12 by the fuel injection device. Execute to stop the operation of the engine 12 . When the fuel cut determination unit 108 determines that a predetermined condition for executing fuel cut control is not satisfied, the engine control unit 102a performs fuel cut control to stop the supply of fuel to the engine 12 by the fuel injection device. The operating state of the engine 12 is continued as non-execution. The fuel cut control corresponds to "control for stopping the internal combustion engine" in the present invention.

From here, the case where the electronic control unit 100 is restarted while the vehicle is running will be described.

The restart determination unit 110 determines whether or not the electronic control unit 100 has been restarted while the vehicle is running. For example, when the vehicle speed V is higher than a predetermined stop vehicle speed value V_stp, it is determined that the vehicle is running. The predetermined stop vehicle speed value V_stp is a predetermined determination value near zero for determining that the vehicle is stopped. Further, when the start signal ST is output by operating the power switch 94 and the electronic control unit 100 is started, it is determined that the electronic control unit 100 has been restarted.

When the restart determination unit 110 determines that the electronic control unit 100 has been restarted while the vehicle is running, the start control unit 102c and the clutch control unit 104 start the engine 12 by executing engine start control. Note that the start control of the engine 12 is executed when the automatic transmission 28 is in the neutral state.

When the engine 12 is started by the start control unit 102c and the clutch control unit 104, the start continuation determination unit 112 determines whether the neutral state of the automatic transmission 28 continues after the engine 12 is started. For example, when the electronic control unit 100 is restarted by operating the power switch 94 after the driver selects the "N operation position" with the shift lever 90, the engine 12 is restarted by the electronic control unit 100 after the restart. If the driver continues to select the "N operating position" after the engine 12 is started, it is determined that the automatic transmission 28 continues to be in the neutral state. On the other hand, when the driver selects an operation position other than the "N operation position" after the engine 12 has started (for example, when the "D operation position" is selected), the automatic transmission 28 is put into the neutral state. determined not to continue.

When the start continuation determination unit 112 determines that the neutral state of the automatic transmission 28 continues, the engine control unit 102a causes the engine 12 to continue operating. When the start continuation determination unit 112 determines that the neutral state of the automatic transmission 28 has not continued, the engine control unit 102a stops the operation of the engine 12. FIG.

FIG. 2 is an example of a flow chart for explaining the control operation of the electronic control unit 100 shown in FIG. The flowchart of FIG. 2 is repeatedly executed while the vehicle is running.

First, in step S10 corresponding to the functions of the restart determination unit 110, the start control unit 102c, and the clutch control unit 104 (hereinafter, the step is omitted), the engine 12 is started by restarting the electronic control unit 100 during running. It is determined whether the control has been executed. If the determination in S10 is affirmative, in S20 corresponding to the function of the start continuation determination unit 112, it is determined whether or not the driver continues to select the "N operation position". If the determination in S10 is negative, the process returns. If the determination in S10 is negative, the engine 12 is started or stopped depending on the vehicle state. For example, the driving force source switching map described above is used to start or stop the engine 12 .

If the determination in S20 is affirmative, in S30 corresponding to the function of the engine control unit 102a, the engine operation continuation request signal requesting the continuation of the operating state of the started engine 12 is set to ON, and the engine 12 continues to operate. is continued and returns. If the determination in S20 is negative, in S40 corresponding to the function of the engine control unit 102a, the engine operation continuation request signal requesting the continuation of the operating state of the started engine 12 is set to OFF, and the engine 12 is not operated. is stopped and returned.

According to this embodiment, (a) the electronic control unit 100 controls the running driving force transmitted from the running driving force source PG to the driving wheels 14, and (b) the electronic control unit 100 controls the automatic transmission. 28 is in a neutral state, the fuel cut control is executed to stop the engine 12; 28 is in a neutral state, and when the neutral state of the automatic transmission 28 continues, the operation of the started engine 12 is continued even if a predetermined condition is satisfied. In this way, the electronic control unit 100 restarted during running starts the engine 12 with the automatic transmission 28 in the neutral state, and when the automatic transmission 28 continues in the neutral state, the engine 12 The operation of the started engine 12 is continued even if a predetermined condition for stopping the engine is established. As a result, if the automatic transmission 28 continues to be in the neutral state, the engine 12 that has been started will not be immediately stopped. easier to recognize.

Although the embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is also applicable to other aspects.

In the above embodiment, the torque converter 24, which is a hydrodynamic transmission device, is provided in the power transmission path PT between the driving force source PG and the automatic transmission 28, but the present invention is in this aspect. is not limited to For example, instead of the torque converter 24, another hydrodynamic transmission device such as a fluid coupling that does not amplify torque may be used. Also, the hydrodynamic transmission device does not necessarily have to be provided, and may be replaced with, for example, a starting clutch.

In the above-described embodiment, the "power transmission device" in the present invention is the automatic transmission 28 that can be brought into a neutral state in which the driving force for traveling output from the driving force source PG for traveling is not transmitted to the drive wheels 14. However, the present invention is not limited to this aspect. For example, the "power transmission device" in the present invention may be the above-described starting clutch provided in place of the torque converter 24, which is a hydraulic transmission device. That is, the “power transmission device” in the present invention may be a clutch that can be put into a neutral state in which the driving force for traveling output from the driving force source PG for traveling is not transmitted to the drive wheels 14 .

In the above-described embodiments, the "control to stop the internal combustion engine" in the present invention was fuel cut control, but the present invention is not limited to this aspect, and the power transmission device is in a neutral state. is established, the internal combustion engine may be stopped. The predetermined condition may be any condition including at least that the power transmission device is in a neutral state.

It should be noted that what has been described above is merely an embodiment of the present invention, and the present invention can be implemented in a mode with various modifications and improvements based on the knowledge of those skilled in the art without departing from the scope of the invention.

10: Hybrid vehicle 12: Engine (internal combustion engine)
14: Drive wheel 28: Automatic transmission (power transmission device)
100: Electronic control device (control device)
MG: Electric motor PG: Driving force source PT: Power transmission path

Claims (1)

An internal combustion engine and an electric motor as a driving force source for running, a power transmission device provided in a power transmission path between the driving force source for running and the drive wheels, and the driving force source for running and the power transmission device. A hybrid vehicle comprising a control device that controls
The control device controls a running driving force transmitted from the running driving force source to the driving wheels,
The control device executes control to stop the internal combustion engine when a predetermined condition including that the power transmission device is in a neutral state is established,
The control device restarted during running starts the internal combustion engine with the power transmission device in a neutral state, and when the power transmission device continues in the neutral state, the predetermined condition is established. A hybrid vehicle characterized in that the operation of the internal combustion engine that has been started is continued even if the vehicle is running.

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