Vehicle control device

Abstract

To provide a control device of a vehicle that has improved both startup responsiveness and speed change performance of an engine when there occurs an engine startup request during speed control of an automatic transmission.SOLUTION: An electronic control device 90 of a vehicle 10 having an engine 12 and an electric motor MG, which are a driving force source for travelling, a K0 clutch 20 disposed between the engine 12 and the electric motor MG, and an automatic transmission 24 disposed between the driving force source for travelling and driving wheels 14 starts cranking of the engine 12 while delaying progress of a torque phase when there occurs a startup request for the engine 12 before a speed change phase of the automatic transmission 24 finishes the torque phase, and then progresses the torque phase, cancelling the delay in the progress of the torque phase, thereby improving both startup responsiveness and speed change performance of the engine 12.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a control device for a vehicle equipped with an engine and an electric motor as driving power sources for driving the vehicle, a clutch disposed between the engine and the electric motor, and an automatic transmission disposed between the driving power source for driving the vehicle and drive wheels. [Background technology]

[0002] In a vehicle equipped with an engine and an electric motor as a driving force source for traveling, a clutch disposed between the engine and the electric motor, and an automatic transmission disposed between the driving force source for traveling and the drive wheels, there is known a technique for simultaneously performing upshift control and engine start control when an engine start request occurs during upshift control of the automatic transmission. For example, one such technique is described in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-149560 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the vehicle control device described in Patent Document 1, automatic transmission upshift control and engine start control are performed simultaneously, so that at the start of the inertia phase of the upshift control, the input torque of the automatic transmission fluctuates in conjunction with engine start, which may result in a deterioration in shift performance (for example, hesitation, which delays the completion of shifting).

[0005] The present invention has been made against the background of the above circumstances, and its object is to provide a vehicle control device that achieves both engine starting responsiveness and gear shifting performance when an engine start request occurs during gear shift control of an automatic transmission. [Means for solving the problem]

[0006] The gist of the first invention is as follows: (a) A control device for a vehicle including an engine and an electric motor as a driving force source for driving the vehicle, a clutch disposed between the engine and the electric motor, and an automatic transmission disposed between the driving force source for driving the vehicle and a driving wheel, (b) When a request to start the engine occurs before the automatic transmission finishes a torque phase, the engine cranking is started while delaying the progress of the torque phase, and then the delay in the progress of the torque phase is released to advance the torque phase. (c) when the engine start request is generated while the torque phase is in progress, the progress of the torque phase is interrupted and the shift phase is returned to a state at the start of the torque phase, thereby delaying the progress of the torque phase; and (d) when the degree of progress of the torque phase at the time when the engine start request is generated is within a predetermined range that is predetermined for each gear stage before and after the shift in the automatic transmission, the progress of the torque phase is delayed. The point is that.

[0009] No. 2 The gist of the invention is as follows: 1 In the invention, the release point for releasing the delay in the progression of the torque phase is set based on the degree of progression of the torque phase at the start point when the delay in the progression of the torque phase begins and the gear stages before and after the shift in the automatic transmission.

[0010] No. 3 The gist of the invention is that in the first invention, when a request to start the engine occurs during the gear shift preparation stage before the start of the torque phase, the start of the torque phase is delayed to slow down the progression of the torque phase. Effect of the Invention

[0011] According to the vehicle control device of the first invention, when a request to start the engine occurs before the automatic transmission has finished the torque phase, the torque phase is delayed and cranking of the engine is started, and then the delay in the torque phase is released and the torque phase is advanced. In this way, the torque phase in the automatic transmission shift control is delayed and the start of engine cranking is prioritized, so that deterioration of engine start responsiveness is suppressed. In addition, since the start of the inertia phase of the shift control is after the start of engine cranking, the input torque of the automatic transmission is suppressed from fluctuating with the start of engine cranking (start of engine start), and a delay in the end of the shift is suppressed. In this way, both the engine start responsiveness and the shift performance are achieved. Furthermore, if the torque phase is in progress when the engine start request is generated, the progress of the torque phase is interrupted and the shift phase is returned to the state at the start of the torque phase, thereby delaying the progress of the torque phase. As a result, if the engine start request is generated when the torque phase is in progress, the progress of the torque phase is interrupted and the shift phase is returned to the state at the start of the torque phase, thereby achieving both suppression of deterioration in engine start responsiveness and suppression of delay in the completion of shifting. Furthermore, when the degree of progress of the torque phase at the time when the engine start request is generated is within a predetermined range that is predefined for each gear stage before and after the shift in the automatic transmission, the progress of the torque phase is delayed. As a result, when the degree of progress of the torque phase at the time when the engine start request is generated is within a predetermined range that is predefined for each gear stage before and after the shift in the automatic transmission, the progress of the torque phase is delayed and the start of engine cranking is prioritized. Whether or not to delay the progress of the torque phase is determined according to the degree of progress of the torque phase at the time when the engine start request is generated, it is easy to achieve both engine start responsiveness and shifting performance.

[0014] No. 2 According to the vehicle control device of the present invention, 1 In the present invention, a release time point for releasing the delay of the torque phase progression is set based on the degree of progression of the torque phase at a start time point when the delay of the torque phase progression is started and the gear stages before and after the shift in the automatic transmission. In this way, since a release time point for releasing the delay of the torque phase progression is set based on the degree of progression of the torque phase at a start time point when the delay of the torque phase progression is started and the gear stages before and after the shift in the automatic transmission, the release time point can be controlled so as not to be too late.

[0015] No. 3 According to the vehicle control device of the first aspect of the invention, when the engine start request occurs during the gear shift preparation stage before the torque phase starts, the start of the torque phase is delayed, thereby delaying the progress of the torque phase. In this way, when the engine start request occurs during the progress of the torque phase, the start of the torque phase is delayed, thereby achieving both suppression of deterioration of engine start responsiveness and suppression of delay in the completion of gear shifting. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic configuration diagram of a vehicle equipped with an electronic control device according to an embodiment of the present invention, and is also a functional block diagram showing essential parts of control functions for various controls in the vehicle. [Diagram 2] 2 is an example of a flowchart illustrating a control operation of the electronic control device shown in FIG. 1. [Diagram 3] 3 is an example of a time chart when the flowchart of FIG. 2 is executed during shift control of a power-on upshift of an automatic transmission during EV driving. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that in the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios and shapes of the various parts are not necessarily drawn accurately. EXAMPLES

[0018] FIG. 1 is a schematic diagram of a vehicle 10 equipped with an electronic control device 90 according to an embodiment of the present invention, and is also a functional block diagram showing the main parts of the control functions for various controls in the vehicle 10.

[0019] The vehicle 10 includes an engine 12 and an electric motor MG, which are driving power sources for traveling, and a power transmission device 16 provided in a power transmission path between the engine 12 and driving wheels 14. The vehicle 10 is a hybrid vehicle.

[0020] The engine 12 is a known internal combustion engine. An engine control device 50 including a throttle actuator, a fuel injection device, an ignition device, and the like provided in the vehicle 10 is controlled by an electronic control device 90 (described later), whereby an engine torque Te [Nm] that is an output torque of the engine 12 is controlled.

[0021] The power transmission device 16 includes, in order from the engine 12 side, a damper 42, a K0 clutch 20, an electric motor connecting shaft 36, a torque converter 22, an automatic transmission 24, and the like, housed within a case 18 which is a non-rotating member attached to the vehicle body. The power transmission device 16 also includes a propeller shaft 28 connected to a transmission output shaft 26 which is an output rotating member of the automatic transmission 24, a differential gear 30 connected to the propeller shaft 28, a pair of drive shafts 32 connected to the differential gear 30, and the like.

[0022] The power transmission device 16 includes an engine connecting shaft 34 that connects the engine 12 and a damper 42. The damper 42 is a well-known damper device, such as a pendulum damper, that transmits the rotation of the engine 12 while absorbing pulsation of the engine 12.

[0023] The K0 clutch 20 is a clutch disposed between the engine 12 and the electric motor MG in the power transmission path between the engine 12 and the drive wheels 14. The electric motor connecting shaft 36 connects the K0 clutch 20 and the torque converter 22. The K0 clutch 20 is a hydraulic friction engagement device constituted by, for example, a multi-plate or single-plate clutch. The K0 clutch 20 switches between an engaged state, a released state, or a controlled state by changing a transmission torque capacity of the K0 clutch 20 (the engagement force of the K0 clutch 20) of the K0 clutch 20, which is a K0 torque PRk0 [Pa] that is a regulated hydraulic pressure supplied from the hydraulic control circuit 56. When the K0 clutch 20 is in an engaged state in the vehicle 10, the engine 12 and the torque converter 22 are connected to each other via the damper 42 and the K0 clutch 20 so as to be capable of transmitting power. On the other hand, when the K0 clutch 20 is in a released state, the power transmission between the engine 12 and the torque converter 22 is interrupted. The K0 clutch 20 functions as a clutch that connects and disconnects the engine 12 and the electric motor MG. When the K0 clutch 20 is in an engaged state, one end of the electric motor connecting shaft 36 is connected to the engine 12 via a damper 42, and is thus rotationally driven by the engine 12. The K0 clutch 20 corresponds to the "clutch" of this invention.

[0024] The torque converter 22 is a well-known torque converter. The torque converter 22 includes a pump wheel 22a connected to the motor connecting shaft 36, a turbine wheel 22b connected to a transmission input shaft 38 that is an input rotating member of the automatic transmission 24, and a lock-up clutch 40 that directly connects the pump wheel 22a and the turbine wheel 22b. The torque converter 22 is a fluid-type power transmission device that transmits the driving force for traveling from each of the driving force sources for traveling (the engine 12, the electric motor MG) from the motor connecting shaft 36 to the transmission input shaft 38 via a fluid. The torque converter 22 is connected to the engine 12 via the K0 clutch 20 and a damper 42. The automatic transmission 24 is connected to the torque converter 22 and is provided in a power transmission path between the torque converter 22 and the drive wheels 14. The torque converter 22 and the automatic transmission 24 each constitute a part of a power transmission path between a driving power source for traveling (the engine 12, the electric motor MG) and the driving wheels 14.

[0025] The electric motor MG is a rotating electric machine having a function as an electric motor that generates mechanical power from electric power and a function as a generator that generates electric power from mechanical power, and is a so-called motor generator. The electric motor MG is connected to a battery 54 provided in the vehicle 10 via an inverter 52 described later. The battery 54 is an electricity storage device that supplies and receives electric power to the electric motor MG. The electric motor MG controls the electric motor torque Tm [Nm], which is the output torque of the electric motor MG, by controlling the inverter 52 by an electronic control device 90 described later. For example, when the rotation direction of the electric motor MG is a positive rotation that is the same as the rotation direction when the engine 12 is in operation, the electric motor torque Tm is a powering torque when it is a positive torque on the acceleration side, and is a regenerative torque when it is a negative torque on the deceleration side. The electric power also means electric energy when there is no particular distinction. The power also means torque and force when there is no particular distinction.

[0026] The electric motor MG is connected to the electric motor connecting shaft 36 in the case 18 so as to be capable of transmitting power. In other words, the electric motor MG is connected to a power transmission path between the K0 clutch 20 and the torque converter 22 so as to be capable of transmitting power. In other words, the electric motor MG is connected to the torque converter 22 and the automatic transmission 24 so as to be capable of transmitting power without passing through the K0 clutch 20.

[0027] The automatic transmission 24 is disposed between the driving power source for traveling (the engine 12 and the electric motor MG) and the drive wheels 14, and is a known planetary gear type automatic transmission including, for example, one or more planetary gear devices (not shown) and a plurality of gear shift engagement devices CB. The gear shift engagement devices CB are, for example, known hydraulic friction engagement devices. The gear shift engagement devices CB have their respective transmission torque capacities, or CB torques Tcb [Nm], changed by the CB hydraulic pressure PRcb [Pa], or regulated hydraulic pressure, supplied from the hydraulic control circuit 56, thereby switching the control state, such as an engaged state or a disengaged state.

[0028] The automatic transmission 24 is a stepped transmission in which one of a plurality of gear stages (also called gear stages) with different speed ratios (also called gear ratios) γat (=AT input rotation speed Ni [rpm] / AT output rotation speed No [rpm]) is formed by engaging one of the engagement devices for shifting CB. The automatic transmission 24 switches the formed gear stages by switching the control state of a predetermined engagement device, which is an engagement device involved in shifting the automatic transmission 24 among the engagement devices for shifting CB, according to the driver's accelerator operation, the vehicle speed V [km / h], etc., by an electronic control device 90 described later. The AT input rotation speed Ni is the rotation speed of the transmission input shaft 38, and is the input rotation speed of the automatic transmission 24. The AT input rotation speed Ni is the same value as the turbine rotation speed Nt [rpm], which is the output rotation speed of the torque converter 22. The AT input rotation speed Ni can be expressed by the turbine rotation speed Nt. The AT output rotation speed No is the rotation speed of the transmission output shaft 26 , and is the output rotation speed of the automatic transmission 24 .

[0029] For example, in the shift control of the automatic transmission 24, a shift is performed by switching one of the shift engagement devices CB between an engaged state and a released state, that is, a so-called clutch-to-clutch shift is performed. Here, the shift engagement device CB that is switched from a released state to an engaged state in the clutch-to-clutch shift is referred to as an "engagement side engagement device CBcon," and the shift engagement device CB that is switched from an engaged state to a released state in the clutch-to-clutch shift is referred to as a "release side engagement device CBdis." In addition, the CB oil pressure PRcb supplied to the hydraulic actuator that controls the engagement / disengagement state of the engagement side engagement device CBcon is referred to as an "engagement side operating oil pressure Pcon[Pa]," and the CB oil pressure PRcb supplied to the hydraulic actuator that controls the engagement / disengagement state of the release side engagement device CBdis is referred to as a "release side operating oil pressure Pdis[Pa]."

[0030] The hydraulic control circuit 56 uses the hydraulic pressure of oil (hydraulic oil OIL) pumped from the MOP 58, which is a mechanical oil pump, or the EOP 60, which is an electric oil pump, as a source pressure to supply the necessary hydraulic oil OIL to each part in the case 18. For example, the hydraulic control circuit 56 is provided with a K0 solenoid valve SC for controlling the connection and disconnection of the K0 clutch 20, and four shift solenoid valves SL1 to SL4 for controlling the shifting of the automatic transmission 24 (hereinafter, referred to as "shift solenoid valves SL" unless otherwise specified). The K0 solenoid valve SC and the shift solenoid valve SL are, for example, well-known linear solenoid valves, and include an electromagnetic part that is a device that converts electrical energy into driving force by supplying a driving current to a solenoid, and a pressure regulating part that regulates the pressure of the hydraulic oil OIL by driving the electromagnetic part to generate hydraulic oil pressure.

[0031] By controlling the drive current of the K0 solenoid valve SC, the hydraulic pressure supplied to the hydraulic actuator that controls the connected / disconnected state of the K0 clutch 20 is adjusted to control the connected / disconnected state of the K0 clutch 20. For example, the K0 clutch 20 is put into a released state by turning off the drive current of the K0 solenoid valve SC (a state in which no drive current flows), and the K0 clutch 20 is put into an engaged state by turning on the drive current of the K0 solenoid valve SC (a state in which drive current flows).

[0032] By controlling the on / off combination of each drive current of the shift solenoid valve SL, the hydraulic pressure supplied to each hydraulic actuator that controls the engagement / disengagement state of the shift engagement device CB provided in the automatic transmission 24 is adjusted. This allows the automatic transmission 24 to be placed in neutral or to form a desired gear ratio γat. The shift engagement device CB is, for example, a wet-type multi-plate hydraulic friction engagement device such as a brake or a clutch.

[0033] In the power transmission device 16, when the K0 clutch 20 is engaged, the power output from the engine 12 is transmitted from the engine connecting shaft 34 to the driving wheels 14 via the K0 clutch 20, the electric motor connecting shaft 36, the torque converter 22, the automatic transmission 24, the propeller shaft 28, the differential gear 30, the drive shaft 32, etc. in this order. The power output from the electric motor MG is transmitted from the electric motor connecting shaft 36 to the driving wheels 14 via the torque converter 22, the automatic transmission 24, the propeller shaft 28, the differential gear 30, the drive shaft 32, etc. in this order, regardless of the control state of the K0 clutch 20.

[0034] The vehicle 10 includes the MOP 58, which is a mechanical oil pump, the EOP 60, which is an electric oil pump, and a pump motor 62. The MOP 58 is connected to the pump impeller 22a, and is rotated by a driving power source for traveling (the engine 12, the electric motor MG) to discharge hydraulic oil OIL used in the power transmission device 16. The pump motor 62 is a motor dedicated to the EOP for rotating the EOP 60. The EOP 60 is rotated by the pump motor 62 to discharge hydraulic oil OIL. The hydraulic oil OIL discharged by the MOP 58 and the EOP 60 is supplied to a hydraulic control circuit 56. The hydraulic control circuit 56 supplies the CB hydraulic pressure PRcb, the K0 hydraulic pressure PRk0, and the like, which are adjusted based on the hydraulic oil OIL discharged by the MOP 58 and / or the EOP 60.

[0035] The vehicle 10 includes an electronic control device 90. The electronic control device 90 includes a so-called microcomputer equipped with, for example, a CPU, RAM, ROM, an input / output interface, and the like, and the CPU executes various controls of the vehicle 10 by performing signal processing according to a program previously stored in the ROM while utilizing the temporary storage function of the RAM. The electronic control device 90 includes computers for engine control, electric motor control, hydraulic control, and the like as necessary. The electronic control device 90 corresponds to the "control device" in the present invention.

[0036] The electronic control device 90 receives various signals based on detection values ​​from various sensors provided in the vehicle 10 (e.g., engine rotation speed sensor 70, turbine rotation speed sensor 72, output rotation speed sensor 74, electric motor rotation speed sensor 76, accelerator opening sensor 78, throttle valve opening sensor 80, battery sensor 84, etc.) (e.g., engine rotation speed Ne [rpm] which is the rotation speed of the engine 12, turbine rotation speed Nt which is the same value as the AT input rotation speed Ni, AT output rotation speed No corresponding to the vehicle speed V, electric motor rotation speed Nm [rpm] which is the rotation speed of the electric motor MG, accelerator opening θacc [%] which is the driver's accelerator operation amount which indicates the magnitude of the driver's acceleration operation, throttle valve opening θth [%] which is the opening of the electronic throttle valve, battery temperature THbat [°C] of the battery 54, battery charge / discharge current Ibat [A], battery voltage Vbat [V], etc.).

[0037] The electronic control device 90 outputs various command signals (e.g., an engine control signal Se for controlling the engine 12, an electric motor control signal Sm for controlling the electric motor MG, a CB hydraulic control signal Sbc for controlling the gear shift engagement device CB, a K0 hydraulic control signal Sk0 for controlling the K0 clutch 20, an LU hydraulic control signal Slu for controlling the lock-up clutch 40, an EOP control signal Seop for controlling the EOP 60, etc.) to each device (e.g., an engine control device 50, an inverter 52, a hydraulic control circuit 56, a pump motor 62, etc.) provided in the vehicle 10.

[0038] The electronic control device 90 functionally comprises a hybrid control means or hybrid control section 92 , a clutch control means or clutch control section 94 , and a gear shift control means or gear shift control section 96 .

[0039] The hybrid control unit 92 functionally comprises an engine control means, i.e., an engine control unit 92a, that controls the operation of the engine 12, and an electric motor control means, i.e., an electric motor control unit 92b, that controls the operation of the electric motor MG via the inverter 52, and performs hybrid drive control using the engine 12 and the electric motor MG, etc., using these control functions.

[0040] The hybrid control unit 92 calculates the drive demand amount of the vehicle 10 by the driver, for example, by applying the accelerator opening θacc and the vehicle speed V to a drive demand amount map. The drive demand amount map is a map in which the relationship between the accelerator opening θacc, the vehicle speed V, and the drive demand amount is obtained in advance experimentally or by design and stored. The drive demand amount is, for example, the required drive torque Trdem [Nm] at the drive wheels 14. In other words, the required drive torque Trdem is the required drive power Prdem [W] at the vehicle speed V at that time. The drive demand amount can also be the required drive force Frdem [N] at the drive wheels 14, the required AT output torque at the transmission output shaft 26, or the like. In calculating the drive demand amount, the AT output rotation speed No, or the like, can be used instead of the vehicle speed V.

[0041] The hybrid control unit 92 outputs an engine control signal Se for controlling the engine 12 and an electric motor control signal Sm for controlling the electric motor MG so as to realize the required driving power Prdem, taking into consideration the transmission loss, the auxiliary load, the gear ratio γat of the automatic transmission 24, the chargeable electric power Win [W] and the dischargeable electric power Wout [W] of the battery 54, etc. The engine control signal Se is, for example, a command value for 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 Sm is, for example, a command value for the power consumption Wm [W] of the electric motor MG that outputs the electric motor torque Tm at the electric motor rotation speed Nm at that time.

[0042] The chargeable power Win of the battery 54 is the maximum power that can be input, which specifies the limit on the input power of the battery 54, and indicates the input limit of the battery 54. The dischargeable power Wout of the battery 54 is the maximum power that can be output, which specifies the limit on the output power of the battery 54, and indicates the output limit of the battery 54. The chargeable power Win and dischargeable power Wout of the battery 54 are calculated by the electronic control device 90 based on, for example, the battery temperature THbat and the state of charge value SOC [%] of the battery 54 (the ratio of the amount of charge actually stored to a predetermined full charge capacity).

[0043] When the required drive torque Trdem can be satisfied only by the output of the electric motor MG, the hybrid control unit 92 sets the drive mode to the motor drive (=EV drive) mode. In the EV drive mode, the hybrid control unit 92 performs EV drive by outputting drive force for drive only from the electric motor MG among the drive force sources for drive (engine 12, electric motor MG) when the K0 clutch 20 is in the disengaged state. On the other hand, when the required drive torque Trdem cannot be satisfied without using at least the output of the engine 12, the hybrid control unit 92 sets the drive mode to the engine drive mode, i.e., hybrid drive (=HV drive) mode. In the HV drive mode, the hybrid control unit 92 performs engine drive by outputting drive force for drive only from the engine 12 among the drive force sources for drive (engine 12, electric motor MG) when the K0 clutch 20 is in the engaged state, i.e., HV drive. On the other hand, even if the required drive torque Trdem can be satisfied only by the output of the electric motor MG, the hybrid control unit 92 establishes the HV driving mode when the state of charge value SOC of the battery 54 falls below a predetermined engine start threshold value or when warming up of the engine 12 or the like is required. The engine start threshold value is a predetermined threshold value for determining that the state of charge value SOC is at a value at which the engine 12 needs to be forcibly started to charge the battery 54. In this way, the hybrid control unit 92 switches between the EV driving mode and the HV driving mode by automatically stopping the engine 12 during HV driving and restarting the engine 12 after the engine has stopped, starting the engine 12 during EV driving, automatically stopping the engine 12 while the vehicle is stopped and restarting the engine 12 after the engine has stopped, based on the required drive torque Trdem, etc.

[0044] The engine control unit 92a controls the engine torque Te to realize a drive demand amount for the vehicle 10. The electric motor control unit 92b controls the electric motor torque Tm to realize a drive demand amount for the vehicle 10. Specifically, in the EV driving mode, the electric motor control unit 92b controls the electric motor torque Tm to realize the required drive torque Trdem. In the HV driving mode, the engine control unit 92a controls the engine torque Te to realize all or a part of the required drive torque Trdem, and the electric motor control unit 92b controls the electric motor torque Tm to compensate for the torque that is insufficient in the engine torque Te for the required drive torque Trdem.

[0045] The hybrid control unit 92 further includes, functionally, a start determination means for determining whether or not the engine 12 should be started, that is, a start determination unit 92c, and a start control means for executing start control of the engine 12, that is, a start control unit 92d.

[0046] The start determination unit 92c determines whether or not a start of the engine 12 has been requested. That is, the start determination unit 92c determines whether or not there is a request to start the engine 12. For example, in the EV driving mode, the start determination unit 92c determines that there is a request to start the engine 12 when (a) the required drive torque Trdem has increased beyond a range that can be covered only by the output of the electric motor MG, (b) warming up of the engine 12, etc. is required, or (c) the state of charge value SOC of the battery 54 is less than the engine start threshold.

[0047] When the start determination unit 92c determines that the start of the engine 12 is requested, the clutch control unit 94 controls the K0 clutch 20 to execute start control of the engine 12. For example, the clutch control unit 94 outputs a K0 hydraulic control signal Sk0 to the hydraulic control circuit 56 for controlling the K0 clutch 20 from a released state toward an engaged state so as to obtain a K0 torque Tk0 for transmitting a cranking torque Tcr, which is a torque that increases the engine rotation speed Ne, to the engine 12 side. The clutch control unit 94 outputs a K0 hydraulic control signal Sk0 to the hydraulic control circuit 56 for controlling the actuator to switch the control state of the K0 clutch 20 from a released state to an engaged state when the engine 12 is started.

[0048] When the start determination unit 92c determines that the start of the engine 12 is requested, the start control unit 92d controls the engine 12 and the electric motor MG to execute start control of the engine 12. For example, the start control unit 92d outputs to the inverter 52 an electric motor control signal Sm for causing the electric motor MG to output the cranking torque Tcr in accordance with the switching of the K0 clutch 20 to the engaged state by the clutch control unit 94. That is, when the engine 12 is started, the start control unit 92d outputs to the inverter 52 an electric motor control signal Sm for controlling the electric motor MG to output the cranking torque Tcr.

[0049] When the start determination unit 92c determines that the start of the engine 12 has been requested, the start control unit 92d outputs an engine control signal Se for starting fuel supply, ignition, and the like to the engine control device 50 in conjunction with cranking of the engine 12 by the K0 clutch 20 and the electric motor MG. That is, when starting the engine 12, the start control unit 92d outputs an engine control signal Se for controlling the engine 12 so that the engine 12 starts operating to the engine control device 50. In this way, when the start determination unit 92c determines that the start of the engine 12 has been requested, the start control unit 92d executes start control of the engine 12.

[0050] When starting the engine 12 during EV driving, the start control unit 92d causes the electric motor MG to output an electric motor torque Tm equivalent to the cranking torque Tcr in addition to the electric motor torque Tm for EV driving, that is, the electric motor torque Tm that generates the drive torque Tr.

[0051] The shift control unit 96 judges whether or not to shift the automatic transmission 24 by using, for example, a shift map which is a predetermined relationship, and outputs a CB hydraulic control signal Sbc to the hydraulic control circuit 56 for executing shift control of the automatic transmission 24 as necessary. The shift map is a predetermined relationship having a shift line for judging whether or not to shift the automatic transmission 24 on a two-dimensional coordinate system having, for example, vehicle speed V and required driving torque Trdem as variables. In the shift map, the AT output rotation speed No or the like may be used instead of the vehicle speed V, and the required driving force Frdem, accelerator opening θacc, throttle valve opening θth or the like may be used instead of the required driving torque Trdem.

[0052] The shift phases (shift stages) of the automatic transmission 24 include a shift preparation phase, a torque phase, and an inertia phase. In the shift preparation phase, for example, prior to the torque phase, the lock-up clutch 40 is switched from an engaged state to a released state in order to suppress shift shock. The torque phase is a phase in which the output torque of the automatic transmission 24 changes during the shift period of the automatic transmission 24 (the period from the start of shift control to the end of shift control). The inertia phase is a phase during the shifting period of the automatic transmission 24 in which the turbine rotation speed Nt, which is equal to the rotation speed of the transmission input shaft 38, which is an input side rotating member in the automatic transmission 24, changes from a theoretical pre-shift turbine rotation speed Nt_pre (theoretical turbine rotation speed Nt calculated from the gear ratio γat in the gear stage before the shift and the vehicle speed V) to a theoretical post-shift turbine rotation speed Nt_post (theoretical turbine rotation speed Nt calculated from the gear ratio γat in the gear stage after the shift and the vehicle speed V). The torque phase is also a period in which the transmission torque capacities of the engagement side engagement device CBcon and the release side engagement device CBdis change.

[0053] When a request to start the engine 12 occurs during EV driving while the gear shift control of the automatic transmission 24 is not being executed, the start control unit 92d executes the start control of the engine 12 as described above. Also, when the gear shift control of the automatic transmission 24 is executed during EV driving while the start control unit 92d is not executing the start control of the engine 12, the gear shift control unit 96 executes the gear shift control as described above.

[0054] Incidentally, there are cases where a request to start the engine 12 is issued during the shift control of the automatic transmission 24 (during the execution of the shift control) during EV running.

[0055] When the start determination unit 92c determines that the start of the engine 12 is requested, the progress determination unit 98 determines whether the torque phase progress degree α [%] at the time when the start request of the engine 12 is generated is within a predetermined range. The torque phase progress degree α is the progress degree of the torque phase in the shift phase. For example, the torque phase progress degree α is expressed as the ratio of the transfer torque capacity Tcb_con to the sum of the transfer torque capacity Tcb_dis of the release side engagement device CBdis and the transfer torque capacity Tcb_con of the engagement side engagement device CBcon {=Tcb_con / (Tcb_dis+Tcb_con)}. The transfer torque capacity Tcb_dis can be calculated based on a map in which the relationship between the release side hydraulic pressure Pdis and the transfer torque capacity Tcb_dis is predetermined experimentally or by design, and the transfer torque capacity Tcb_con can be calculated based on a map in which the relationship between the engagement side hydraulic pressure Pcon and the transfer torque capacity Tcb_con is predetermined experimentally or by design. When the shift phase is in the shift preparation stage, the torque phase progress degree α is 0[%], and when the shift phase is the inertia phase, the torque phase progress degree α is 100[%]. The predetermined range is a range of the torque phase progress degree α that is predetermined for determining that the progress of the torque phase, which is the shift phase, is to be delayed, and is, for example, a range that is predetermined for each gear stage before and after the shift in the automatic transmission 24. For example, the lower limit value and the upper limit value of the predetermined range are set so that even if cranking of the engine 12 is started after the determination by the progress degree determination unit 98, the fluctuation of the input torque of the automatic transmission 24 at the start of the inertia phase is small and the delay in the shift completion is within an acceptable range. For example, compared to when the gear stages before and after the shift are on the low-speed side with a large gear ratio γat, when the gear stages before and after the shift are on the high-speed side with a small gear ratio γat, the shift period is short, and therefore the effect on hesitation, which causes the shift completion to be delayed, is small. Therefore, the higher the speed ratio γat in the gears before and after the shift is, the narrower the predetermined range is set, i.e., the lower limit of the predetermined range is set lower and the lower limit of the predetermined range is set higher. In this embodiment, the lower limit of the predetermined range is set to a value equal to or greater than 0[%], and the upper limit of the predetermined range is set to a value slightly lower than 100[%] (see FIG. 3).The "progression of the torque phase" means that the shift control is advanced in the torque phase, that is, the torque phase progress degree is increased. Note that the torque phase progress degree α corresponds to the "progression degree of the torque phase" in the present invention.

[0056] When the progress degree determination unit 98 determines that the torque phase progress degree α at the time when the start request of the engine 12 is generated is within a predetermined range, the shift control unit 96 delays the progress of the torque phase, and the start control unit 92d starts cranking the engine 12. Specifically, the shift control unit 96 interrupts and restores the progress of the torque phase once started in the automatic transmission 24, that is, returns the shift phase to the state at the start time of the torque phase. The shift control unit 96 sets the release time of the delay of the torque phase progress based on a map in which the relationship between the torque phase progress degree α at the delay start time when the delay of the torque phase progress starts, the gear stages before and after the shift in the automatic transmission 24, and the release time (= delay start time + delay period) at which the delay of the torque phase progress is released is predetermined by experiment or design. The delay start time corresponds to the "start time when the delay of the torque phase progress starts" in the present invention. When the time point for canceling the delay in the progression of the torque phase has passed, the gear shift control section 96 cancels the delay in the progression of the torque phase, advances the torque phase, and resumes gear shift control.

[0057] If the progress determination unit 98 determines that the torque phase progress degree α at the time when a request to start the engine 12 is generated is not within a predetermined range, the shift control unit 96 continues shift control, such as by advancing the torque phase, and the start control unit 92d initiates cranking of the engine 12.

[0058] Fig. 2 is an example of a flowchart illustrating the control operation of the electronic control device 90 shown in Fig. 1. The flowchart in Fig. 2 is repeatedly executed during the shift control of the automatic transmission 24 during EV driving.

[0059] First, in step S10 (hereinafter, the term "step" will be omitted) corresponding to the function of the start determination unit 92c, it is determined whether or not a request to start the engine 12 has been generated. If the determination in S10 is positive, it is determined in S20, which corresponds to the function of the progress determination unit 98, whether or not the torque phase progress degree α at the time when the request to start the engine 12 was generated is within a predetermined range. If the determination in S10 is negative, the shift control of the automatic transmission 24 is continued in S30, which corresponds to the function of the shift control unit 96, and then the process returns.

[0060] If the determination in S20 is positive, in S40, which corresponds to the functions of the shift control section 96 and the start control section 92d, the progress of the torque phase is delayed while cranking of the engine 12 is started, and then S50 is executed. In S50, which corresponds to the function of the shift control section 96, the delay in the progress of the torque phase is released, shift control is performed, and then the process returns. If the determination in S20 is negative, in S60, which corresponds to the functions of the shift control section 96 and the start control section 92d, shift control of the automatic transmission 24 is continued and cranking of the engine 12 is started, and then the process returns.

[0061] Fig. 3 is an example of a time chart in which the flowchart in Fig. 2 is executed during shift control of a power-on upshift of the automatic transmission 24 during EV driving. The horizontal axis in Fig. 3 represents time t [ms]. A power-on upshift is an upshift that is executed when the accelerator opening θacc is increased by the driver's accelerator operation (e.g., depressing the accelerator pedal).

[0062] In Fig. 3, the engine operation signal is a signal that controls the operating state of the engine 12, and ON is a control signal that puts the engine 12 in an operating state, and OFF is a control signal that puts the engine 12 in a stopped state. In Fig. 3, the delay period setting signal is a signal that indicates the start time of the delay of the progression of the torque phase when it is switched from OFF to ON, and indicates the release time of the delay of the progression of the torque phase when it is switched from OFF to ON. In Fig. 3, the start setting signal is a "signal that indicates the start time of the set torque phase", and the timing that it is switched from OFF to ON indicates the start time of the torque phase, and the end setting signal is a "signal that indicates the end time of the set torque phase", and the timing that it is switched from OFF to ON indicates the end time of the torque phase.

[0063] In the torque phase progression degree α, the electric motor rotation speed Nm, the turbine rotation speed Nt, the engagement side hydraulic pressure Pcon, and the release side hydraulic pressure Pdis shown in FIG. 3, the present embodiment in which the progression of the torque phase is delayed is shown by a solid line, and a comparative example in which the progression of the torque phase is not delayed is shown by a dashed line.

[0064] The time chart of this embodiment will now be described.

[0065] Before time t1, the lock-up clutch 40 is engaged during EV driving, and the motor rotation speed Nm is increasing due to the driver's accelerator operation. At time t1, a gear shift preparation stage in the power-on upshift gear shift control is started. As part of the gear shift preparation stage, the lock-up clutch 40 is switched from an engaged state to a released state. By switching the lock-up clutch 40 to the released state, the motor connecting shaft 36 and the transmission input shaft 38 are connected via a fluid, and at time t2 (>t1), the motor rotation speed Nm of the electric motor MG, which is the driving force source for driving, begins to become higher than the turbine rotation speed Nt.

[0066] At time t3 (>t2) after the lock-up clutch 40 is switched to the released state, the start setting signal is switched from OFF to ON. In synchronization with the timing of the switching of the start setting signal from OFF to ON, a decrease control is started to decrease the release side hydraulic pressure Pdis and an increase control is started to increase the engagement side hydraulic pressure Pcon, thereby starting the torque phase in the shift control. As a result, the torque phase progress degree α gradually increases from time t3.

[0067] At time t4 (>t3), a request to start the engine 12 is generated, the engine operation signal is switched from OFF (stopped) to ON (operating), and cranking of the engine 12 is started. At time t4, which is the time when the request to start the engine 12 is generated, the torque phase progress degree α is within a predetermined range. Therefore, at time t4, the delay period setting signal is switched from OFF to ON, and the delay of the progress of the torque phase is started. Time t4 is the delay start time. Specifically, the release side hydraulic pressure Pdis is quickly returned to the hydraulic pressure at the start of the decrease control at a predetermined rate, and the engagement side hydraulic pressure Pcon is quickly returned to the hydraulic pressure at the start of the increase control at a predetermined rate, that is, the progress of the torque phase is delayed and the shift phase is returned to the state at the start of the torque phase.

[0068] At time t6 (>t4), the delay period setting signal is switched from on to off, the delay in the progression of the torque phase is released, and the torque phase is advanced. Time t6 corresponds to the "release time point for releasing the delay in the progression of the torque phase" in the present invention. At time t7 (>t6), the end setting signal is switched from off to on. In accordance with the timing of the end setting signal switching from off to on, the decrease control of the release side hydraulic pressure Pdis is ended and the increase control of the engagement side hydraulic pressure Pcon is ended, and the torque phase in the shift control is ended. In the period from time t6 to time t7 (>t6), the torque phase is advanced and the torque phase advancement degree α changes from 0 [%] to 100 [%]. The inertia phase begins at time t7, and during the period from time t7 to time t9 (>t7), the turbine rotation speed Nt corresponding to the vehicle speed V decreases from the theoretical pre-shift turbine rotation speed Nt_pre to the theoretical post-shift turbine rotation speed Nt_post, and the inertia phase ends at time t9.

[0069] In the period from time t9 to time t10 (>t9), the lock-up clutch 40 is switched from the released state to the engaged state, causing the turbine rotation speed Nt to increase toward the motor rotation speed Nm of the electric motor MG, which is the driving force source for traveling.

[0070] In this way, the cranking of the engine 12 starts before time t7 when the inertia phase starts, and preferably the cranking of the engine 12 also ends before time t7 when the inertia phase starts. If the cranking of the engine 12 ends before time t7 when the inertia phase starts, the input torque of the automatic transmission 24 is suppressed from fluctuating due to the cranking of the engine 12, including the start of the cranking of the engine 12, at the start of the inertia phase, so that a delay in the end of the gear shift is suppressed.

[0071] The following describes a time chart of a comparative example. The time chart of this comparative example is substantially the same as the time chart of the embodiment described above, but differs in that the torque phase progression degree α at time t4, when a request to start the engine 12 is generated, is within a predetermined range, and the torque phase progression is not delayed. Therefore, the following description will focus on the parts that are different from the embodiment, and the parts that are substantially the same as the embodiment will be denoted by the same reference numerals and will not be described as appropriate.

[0072] In the comparative example, at time t4, the release side hydraulic pressure Pdis is controlled to decrease, and the engagement side hydraulic pressure Pcon is controlled to increase, that is, the progress of the torque phase is not delayed. As a result, in the period from time t4 to time t5 (>t4), the torque phase is advanced and the torque phase advancement degree α changes from 0[%] to 100[%]. The inertia phase starts at time t5, and in the period from time t5 to time t8 (>t5), the turbine rotation speed Nt corresponding to the vehicle speed V decreases from the theoretical pre-shift turbine rotation speed Nt_pre to the theoretical post-shift turbine rotation speed Nt_post, and the inertia phase ends at time t8.

[0073] In this comparative example, the cranking of the engine 12 ends after time t5 when the inertia phase starts. Therefore, at time t5, the cranking of the engine 12 starts. In Fig. 3, the input torque of the automatic transmission 24 fluctuates with the start of the cranking of the engine 12 (start of the engine 12) at the start of the inertia phase, and, for example, hesitation that causes a delay in the end of the shift is not shown, but there is a risk of hesitation occurring.

[0074] According to this embodiment, when a request to start the engine 12 occurs before the shift phase of the automatic transmission 24 ends the torque phase, the progress of the torque phase is delayed and cranking of the engine 12 is started, and then the delay in the progress of the torque phase is released and the torque phase is advanced. In this way, the progress of the torque phase in the shift control of the automatic transmission 24 is delayed while the start of cranking of the engine 12 is prioritized, so that the deterioration of the start responsiveness of the engine 12 is suppressed. In addition, since the start of the inertia phase of the shift control is after the cranking of the engine 12 has started, the input torque of the automatic transmission 24 is suppressed from fluctuating with the start of cranking of the engine 12, and a delay in the end of the shift is suppressed. In this way, both the start responsiveness and the shift performance of the engine 12 are achieved.

[0075] According to this embodiment, if the torque phase is in progress when a start request for the engine 12 is generated, the progress of the torque phase is interrupted and the shift phase is returned to the state at the start of the torque phase, thereby delaying the progress of the torque phase. In this way, if the torque phase is in progress when a start request for the engine 12 is generated, the progress of the torque phase is interrupted and the shift phase is returned to the state at the start of the torque phase, so that it is possible to both suppress deterioration of the start responsiveness of the engine 12 and suppress delays in the completion of the shift.

[0076] According to this embodiment, the progression of the torque phase is delayed when the torque phase progression degree α at the time when a start request for the engine 12 is generated is within a predetermined range that is previously set for each gear stage before and after the shift in the automatic transmission 24. In this way, when the torque phase progression degree α at the time when a start request for the engine 12 is generated is within a predetermined range that is previously set for each gear stage before and after the shift in the automatic transmission 24, the progression of the torque phase is delayed while priority is given to starting the cranking of the engine 12. Whether or not to delay the progression of the torque phase is determined according to the torque phase progression degree α at the time when a start request for the engine 12 is generated, it is easy to achieve both the starting responsiveness and the shifting performance of the engine 12.

[0077] According to this embodiment, the release time point for releasing the delay in the torque phase progression is set based on the torque phase progression degree α at the start time point when the delay in the torque phase progression is started and the gear stages before and after the shift in the automatic transmission 24. In this way, since the release time point for releasing the delay in the torque phase progression is set based on the torque phase progression degree α at the start time point when the delay in the torque phase progression is started and the gear stages before and after the shift in the automatic transmission 24, it is possible to control so that the release time point is not too late.

[0078] According to this embodiment, if a request to start the engine 12 occurs during the gear shift preparation stage before the start of the torque phase, the start of the torque phase is delayed, thereby slowing down the progress of the torque phase. In this way, if a request to start the engine 12 occurs during the progress of the torque phase, the start of the torque phase is delayed, so that it is possible to both suppress deterioration of the start responsiveness of the engine 12 and suppress delays in the completion of gear shifting.

[0079] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the present invention can be applied to other embodiments.

[0080] In the above embodiment, a case where a request to start the engine 12 occurs while the automatic transmission 24 is in the torque phase in the time chart of FIG. 3 is illustrated, but the present invention is not limited to this example. For example, the present invention is also applicable to a case where a request to start the engine 12 occurs while the automatic transmission 24 is in the shift preparation stage. In this case, even if the shift preparation stage ends, the start of the torque phase is delayed and the cranking of the engine 12 is started, and then the torque phase is advanced. Thus, the "delay" of the progression of the torque phase in the present invention includes both a case where the progression of the torque phase that has once started is interrupted and resumed, and a case where the start of the torque phase that has not yet started is delayed.

[0081] In the above embodiment, the progress of the torque phase is delayed when the torque phase progress degree α at the time when the start request of the engine 12 is generated is within a predetermined range that is set in advance for each gear stage before and after the shift in the automatic transmission 24. However, the present invention is not limited to this embodiment. For example, a predetermined range may not be set, and the progress of the torque phase may be delayed when the start request of the engine 12 is generated while the torque phase is in progress. Even in such an embodiment, the start response of the engine 12 is suppressed from deteriorating because the start of cranking of the engine 12 is prioritized while the progress of the torque phase in the shift control in the automatic transmission 24 is delayed. In addition, the input torque of the automatic transmission 24 is suppressed from fluctuating with the engine start at the start of the inertia phase of the shift control, so that the delay in the end of the shift is suppressed. In this way, both the start response and the shift performance of the engine 12 are achieved.

[0082] In the above embodiment, the release time point for releasing the delay in the torque phase progression is set based on the torque phase progression degree α at the start time point when the delay in the torque phase progression is started and the gear stages before and after the shift in the automatic transmission 24, but the present invention is not limited to this. For example, the release time point may be determined in advance experimentally or by design, regardless of the torque phase progression degree α at the start time point when the delay in the torque phase progression is started and the gear stages before and after the shift in the automatic transmission 24, as long as it is set so that cranking of the engine 12 is not started at the start time point of the inertia phase.

[0083] In the above-described embodiment, the automatic transmission 24 is of the planetary gear type, but the automatic transmission in the present invention may be a stepped transmission of other configurations, such as a constant meshing parallel shaft type.

[0084] In the above-described embodiment, the time chart of FIG. 3 corresponds to a case where a request to start the engine 12 occurs during the power-on upshift shift control of the automatic transmission 24. However, the present invention is also applicable to a case where a request to start the engine 12 occurs during other shift controls, not limited to the power-on upshift.

[0085] In the above embodiment, the torque converter 22 is used as the fluid transmission device, but the present invention is not limited to this embodiment. For example, other fluid transmission devices, such as a fluid coupling that does not amplify torque, may be used as the fluid transmission device instead of the torque converter 22. Also, the fluid transmission device does not necessarily have to be provided, and may be replaced with, for example, a starting clutch.

[0086] It should be noted that the above is merely an embodiment of the present invention, and the present invention can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit of the present invention. [Explanation of symbols]

[0087] 10: Vehicle 12: Engine 14: Drive wheel 20:K0 clutch (clutch) 24: Automatic transmission 90: Electronic control device (control device) MG: Electric motor α: Torque phase progression (torque phase progression)

Claims

1. A control device for a vehicle including an engine and an electric motor as a driving force source for driving the vehicle, a clutch disposed between the engine and the electric motor, and an automatic transmission disposed between the driving force source for driving the vehicle and a driving wheel, When a request to start the engine occurs before a torque phase of a shift phase of the automatic transmission ends, the engine cranking is started while delaying the progression of the torque phase, and then the delay of the progression of the torque phase is released to advance the torque phase; When the engine start request occurs while the torque phase is in progress, the progress of the torque phase is interrupted and the shift phase is returned to a state at the start of the torque phase, thereby delaying the progress of the torque phase; When a degree of progress of the torque phase at the time when a start request for the engine is generated is within a predetermined range that is set in advance for each gear stage before and after a shift in the automatic transmission, the progress of the torque phase is delayed. A vehicle control device comprising:

2. A release time point for releasing the delay in the progress of the torque phase is set based on the degree of progress of the torque phase at a start time point when the delay in the progress of the torque phase is started and the gear stages before and after the shift in the automatic transmission.

2. The vehicle control device according to claim 1.

3. When the engine start request occurs during a shift preparation stage before the start of the torque phase, the start of the torque phase is delayed to slow down the progress of the torque phase.

2. The vehicle control device according to claim 1.

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