JP7622545B2 - Vehicle control device - Google Patents

Description

The present invention relates to a control device for a vehicle equipped with a mechanical transmission device that transmits driving force from a driving force source including an electric motor.

A control device for a vehicle that includes an electric motor and a mechanical transmission device having a predetermined engagement device, in which a driving position that allows the transmission of driving force from the electric motor when the predetermined engagement device is engaged is formed as a shift position. For example, the hybrid vehicle drive device described in Patent Document 1 is such a device. Patent Document 1 discloses that the predetermined engagement device is released when switching from a state in which the mechanical transmission device selects a driving position to a state in which the mechanical transmission device selects a non-driving position in which the driving force from the electric motor cannot be transmitted, and that the released predetermined engagement device is independently engaged when switching from a state in which the non-driving position is selected to a state in which the driving position is selected, thereby quickly engaging the predetermined engagement device.

JP 2015-217914 A

When switching the mechanical transmission to the travel position, it is possible to increase the command pressure of the predetermined engagement device stepwise from the start of engagement to, for example, a maximum pressure, and then to quickly engage the predetermined engagement device, and then to increase the rotation speed of the electric motor to output creep torque. At this time, if torque is input to the mechanical transmission, there is a risk of an engagement shock occurring, so it is preferable to increase the command pressure of the predetermined engagement device when no torque is input to the mechanical transmission. Also, during the transitional period in which the rotation speed of the electric motor is increased, the backlash formed between the gears constituting the mechanical transmission is eliminated, and there is a risk of a shock occurring due to the impact when the backlash is eliminated. Therefore, it is preferable to appropriately control the electric motor and perform backlash elimination control to reduce the shock occurring when the backlash is eliminated. Here, when the driver operates the accelerator after the switching operation, if the torque is output from the electric motor after waiting for the rotation speed of the electric motor to increase, there is a risk of a delay in the output of the torque in response to the accelerator operation, which may cause the driver to feel uncomfortable. On the other hand, if the rotational speed of the electric motor is increased from the point when the accelerator is operated and torque is output from the electric motor, a shock occurs because the specified engagement device is rapidly engaged while torque is being input to the mechanical transmission device.

The present invention was made against the background of the above circumstances, and its purpose is to provide a control device for a vehicle equipped with an electric motor and a mechanical transmission that can ensure responsiveness to accelerator operation while suppressing the occurrence of shocks, even if the accelerator is operated when switching the mechanical transmission to the driving position.

The gist of the first invention is a control device for a vehicle including (a) an electric motor and a mechanical transmission device having a predetermined engagement device, the predetermined engagement device being brought into an engaged state to form a driving position in which a driving force from the electric motor can be transmitted as a shift position, (b) an electric motor control unit that controls the rotation speed of the electric motor to be equal to or higher than a predetermined rotation speed, and causes the electric motor to output a predetermined torque that generates a creep phenomenon, and (c) when a predetermined switching operation is performed by the driver from a state in which a different shift position different from the driving position of the mechanical transmission device is selected to a state in which the driving position is selected, the output of the predetermined torque is stopped, and a command pressure of the predetermined engagement device is increased in a stepwise manner to quickly engage the predetermined engagement device, and then the rotation speed of the electric motor is increased to the predetermined The system includes a garage control unit that executes rapid garage control to increase the rotational speed of the electric motor to above the predetermined rotational speed; and (d) a backlash elimination control unit that executes backlash elimination control to control the rotational speed of the electric motor so as to reduce shocks that occur when backlash formed on the power transmission path of the mechanical transmission device is eliminated during a transitional period in which the garage control unit increases the rotational speed of the electric motor, and (e) the garage control unit continues the rapid garage control until the rotational speed of the electric motor starts to increase when the driver operates the accelerator during the execution of the rapid garage control and before the backlash elimination control is started, and increases the rotational speed of the electric motor to above the predetermined rotational speed without executing the backlash elimination control during the transitional period in which the rotational speed of the electric motor is increased.

The gist of the second invention is that in the first invention, the garage control unit increases the rotation speed of the electric motor to or above the predetermined rotation speed without executing the backlash elimination control when the amount of operation of the accelerator is equal to or greater than a predetermined amount.

The gist of the third invention is that in the first or second invention, the garage control unit executes the rapid garage control when the driver performs the predetermined switching operation in a motor driving mode in which the vehicle can run using the driving force from the electric motor with the engine of the vehicle stopped.

The gist of the fourth invention is that in any one of the first to third inventions, when the driver performs the predetermined switching operation while the electric motor is outputting the predetermined torque, the garage control unit executes the rapid garage control while temporarily stopping the output of the predetermined torque.

The gist of the fifth invention is that in any one of the first to fourth inventions, the garage control unit drives an electric oil pump provided on the vehicle while the quick garage control is being performed, and controls the engagement hydraulic pressure of the predetermined engagement device using the hydraulic pressure of the hydraulic oil discharged from the electric oil pump as the base pressure.

According to the first invention, even if the driver operates the accelerator while rapid garage control is being executed and before backlash elimination control is started, rapid garage control continues, suppressing shocks caused by interrupting rapid garage control. On the other hand, the rotation speed of the electric motor is increased without executing backlash elimination control, which is executed during the transitional period when the rotation speed of the electric motor is increased, and therefore responsiveness to accelerator operation can be increased accordingly. This makes it possible to achieve both suppression of shocks that occur during switching operations and responsiveness to accelerator operation.

According to the second invention, when the amount of accelerator operation is equal to or greater than a predetermined amount, the rotation speed of the electric motor is increased without executing backlash elimination control, and when the amount of accelerator operation is less than the predetermined amount, backlash elimination control is executed during the transitional period when the rotation speed of the electric motor increases. As a result, by appropriately setting the predetermined amount relative to the amount of accelerator operation, it is possible to execute backlash elimination control by prioritizing the suppression of shock when, for example, the amount of accelerator operation by the driver is small.

According to the third invention, when a predetermined switching operation is performed in the motor drive mode in which the vehicle can run on the driving force from the electric motor while the engine is stopped, the rapid garage control is executed, so that the rapid garage control is executed appropriately when a predetermined torque that causes the creep phenomenon is output from the electric motor.

According to the fourth invention, when a predetermined switching operation is performed while a predetermined torque is being output from the electric motor, the rapid garage control is executed in a state where the predetermined torque is temporarily stopped, so that the rapid garage control is executed appropriately.

According to the fifth aspect of the invention, when rapid garage control is being performed, the electric oil pump is driven, so that the hydraulic pressure of the hydraulic oil discharged from the electric oil pump can be used as the source pressure to realize the command pressure of the specified engagement device.

1 is a diagram illustrating a schematic configuration of a vehicle to which the present invention is applied, and is also a diagram illustrating main parts of control functions and a control system for various controls in the vehicle. 4 is a flowchart illustrating a main part of the control operation of the electronic control device, and is a flowchart illustrating the control operation when the driver operates the accelerator after garage operation. 3 is a time chart when the control operation shown in the flowchart of FIG. 2 is executed.

The following describes in detail the embodiments of the present invention with reference to the drawings. Note that in the following embodiments, the drawings have been simplified or modified as appropriate, and the dimensional ratios and shapes of each part are not necessarily drawn accurately.

Figure 1 is a diagram illustrating the general configuration of a vehicle 10 to which the present invention is applied, as well as a diagram illustrating the main parts of the control functions and control system for various controls in the vehicle 10. In Figure 1, the vehicle 10 is a hybrid vehicle equipped with an engine 12 and an electric motor MG, which are driving power sources for traveling. The vehicle 10 also has drive wheels 14, and a power transmission device 16 provided in the power transmission path between the engine 12 and the electric motor MG and the drive wheels 14.

The engine 12 is a known internal combustion engine such as a gasoline engine or a diesel engine. The engine 12 has an engine control device 50, which includes a throttle actuator, a fuel injection device, an ignition device, and the like, provided on the vehicle 10, controlled by an electronic control device 90 (described later), thereby controlling the engine torque Te, which is the output torque of the engine 12.

The electric motor MG is a rotating electric machine that functions as a motor to generate mechanical power from electric power and as a generator to generate 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 provided in the vehicle 10. 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 MG torque Tm, 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 the same as the rotation direction when the engine 12 is operating, the MG torque Tm is a power torque when it is a positive torque on the acceleration side, and a regenerative torque when it is a negative torque on the deceleration side. The electric power is also the same as electric energy when there is no particular distinction. The power is also the same as torque and force when there is no particular distinction.

The power transmission device 16 includes a K0 clutch 20, a torque converter 22, an automatic transmission 24, and the like, in a case 18, which is a non-rotating member attached to the vehicle body. The K0 clutch 20 is a clutch provided between the engine 12 and the electric motor MG in the power transmission path between the engine 12 and the drive wheels 14. The torque converter 22 is connected to the engine 12 via the K0 clutch 20. The automatic transmission 24 is connected to the torque converter 22 and is interposed in the 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 the power transmission path between the drive power source (engine 12, electric motor MG) and the drive wheels 14. 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, and a pair of drive shafts 32 connected to the differential gear 30. The power transmission device 16 also includes an engine connecting shaft 34 that connects the engine 12 and the K0 clutch 20, and an electric motor connecting shaft 36 that connects the K0 clutch 20 and the torque converter 22.

The electric motor MG is connected to the electric motor connecting shaft 36 inside the case 18 so that the power can be transmitted. In other words, the electric motor MG is connected to the power transmission path between the K0 clutch 20 and the torque converter 22 so that the power can be transmitted. In other words, the electric motor MG is connected to the torque converter 22 and the automatic transmission 24 so that the power can be transmitted without going through the K0 clutch 20.

The torque converter 22 includes a pump wheel 22a connected to the motor connecting shaft 36, and a turbine wheel 22b connected to the transmission input shaft 38, which is an input rotating member of the automatic transmission 24. The torque converter 22 is a fluid-type transmission device that transmits driving force from each of the driving force sources (engine 12, electric motor MG) to the automatic transmission 24 via fluid. The torque converter 22 includes an LU clutch 40 that serves as a direct-coupled clutch that connects the pump wheel 22a and the turbine wheel 22b, i.e., that connects the motor connecting shaft 36 and the transmission input shaft 38. The LU clutch 40 is a known lock-up clutch.

The automatic transmission 24 is a known planetary gear type automatic transmission that includes, for example, one or more planetary gear devices (not shown) and multiple engagement devices CB. The engagement devices CB are, for example, known hydraulic friction engagement devices. The engagement devices CB have their respective torque capacities, or CB torque Tcb, changed by the CB hydraulic pressure PRcb, which is a regulated hydraulic pressure supplied from the hydraulic control circuit 56, thereby switching between operating states, or control states, such as an engaged state or a disengaged state.

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/AT output rotation speed No) is formed by engaging one of the engagement devices CB. The automatic transmission 24 switches the gear stages formed by switching the control state of the engagement devices CB involved in the shifting of the automatic transmission 24 according to the driver's accelerator operation, vehicle speed V, etc. by the electronic control device 90 described later. In other words, in the shift control of the automatic transmission 24, a so-called clutch-to-clutch shift is performed in which the shift is performed by, for example, releasing the release side engagement device and engaging the engagement side engagement device. The release side engagement device is an engagement device that was in an engaged state before the shifting of the automatic transmission 24 among the engagement devices involved in the shifting, and is an engagement device that is controlled from the engaged state to the released state during the shifting transition of the automatic transmission 24. The engaging side engaging device is an engaging device that is in a disengaged state before the automatic transmission 24 is shifted among the engaging devices involved in the shift, and is an engaging device that is controlled from the disengaged state to the engaged state during the shift transition of the automatic transmission 24. 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, which is the output rotation speed of the torque converter 22. The AT input rotation speed Ni can be expressed as 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.

The K0 clutch 20 is a hydraulic friction engagement device that is composed of, for example, a multi-plate or single-plate clutch. The K0 clutch 20 switches between control states such as an engaged state and a released state by changing the torque capacity of the K0 clutch 20, K0 torque Tk0, using the regulated hydraulic pressure, K0 hydraulic pressure PRk0, supplied from the hydraulic control circuit 56.

In the vehicle 10, when the K0 clutch 20 is engaged, the engine 12 and the torque converter 22 are connected so that power can be transmitted. On the other hand, when the K0 clutch 20 is disengaged, power transmission between the engine 12 and the torque converter 22 is interrupted. Since the electric motor MG is connected to the torque converter 22, the K0 clutch 20 functions as a clutch that connects and disconnects the engine 12 from the electric motor MG.

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 drive 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 addition, the power output from the electric motor MG is transmitted from the electric motor connecting shaft 36 to the drive wheels 14 via the torque converter 22, the automatic transmission 24, the propeller shaft 28, the differential gear 30, the drive shaft 32, etc., regardless of the control state of the K0 clutch 20.

The vehicle 10 further includes a mechanical oil pump MOP58, an electric oil pump EOP60, and a pump motor 62. The MOP58 is connected to the pump impeller 22a and is rotated by a driving force source (engine 12, 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 EOP60 for rotating the EOP60. The EOP60 is rotated by the pump motor 62 to discharge hydraulic oil OIL. The hydraulic oil OIL discharged by the MOP58 and EOP60 is supplied to the 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 at least one of the MOP58 and EOP60.

The vehicle 10 further includes an electronic control device 90 that includes a control device for the vehicle 10. The electronic control device 90 includes a so-called microcomputer that includes, 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, etc., as necessary.

The electronic control unit 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, MG rotation speed sensor 76, accelerator opening sensor 78, throttle valve opening sensor 80, brake pedal sensor 82, battery sensor 84, oil temperature sensor 86, shift position sensor 88, etc.) (e.g., engine rotation speed Ne, 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, which corresponds to the vehicle speed V, MG rotation speed Nm, which is the rotation speed of the electric motor MG, etc.). , accelerator opening θacc, which is the amount of accelerator operation by the driver that indicates the magnitude of the driver's acceleration operation, throttle valve opening θth, which is the opening of the electronic throttle valve, brake-on signal Bon, which is a signal indicating the state in which the brake pedal for operating the wheel brakes is being operated by the driver, battery temperature THbat, battery charge/discharge current Ibat, and battery voltage Vbat of battery 54, hydraulic oil temperature THoil, which is the temperature of the hydraulic oil OIL in the hydraulic control circuit 56, and operating position (=operating position) POSop, which indicates the position to which the shift lever 64 provided on the vehicle 10 is operated, are respectively supplied.

The shift lever 64 is a shift operation member that is operated by the driver to one of a plurality of operation positions POSop. The operation position POSop is a signal that indicates the state in which one of a plurality of shift positions (=shift positions) of the automatic transmission 24 is selected, and includes, for example, the P, R, N, and D operation positions. The shift positions of the automatic transmission 24 include, for example, the P, R, N, and D positions.

The P operating position is a parking operating position that selects the P position, which is the parking position (=parking position) of the automatic transmission 24. The P position of the automatic transmission 24 is a shift position of the automatic transmission 24 in which the automatic transmission 24 is in a neutral state and the rotation of the transmission output shaft 26 is mechanically prevented. The neutral state of the automatic transmission 24 is a state in which the automatic transmission 24 cannot transmit driving force, and is achieved, for example, by disengaging all of the engagement devices CB and cutting off the power transmission in the automatic transmission 24. The state in which the rotation of the transmission output shaft 26 is mechanically prevented is a parking lock state in which the transmission output shaft 26 is fixed so as not to rotate by a known parking lock mechanism provided in the vehicle 10.

The R operating position is a reverse driving operating position that selects the R position, which is the reverse driving position (= reverse driving position) of the automatic transmission 24. The R position of the automatic transmission 24 is a shift position of the automatic transmission 24 that allows the vehicle 10 to drive in reverse.

The N operating position is a neutral operating position that selects the N position, which is the neutral position (=neutral position) of the automatic transmission 24. The N position of the automatic transmission 24 is a shift position of the automatic transmission 24 in which the automatic transmission 24 is in a neutral state.

The D operating position is a forward driving operating position that selects the D position, which is the forward driving position (= forward driving position) of the automatic transmission 24. The D position of the automatic transmission 24 is a shift position of the automatic transmission 24 that executes automatic shift control of the automatic transmission 24 to enable forward driving of the vehicle 10.

The P position and N position of the automatic transmission 24 are non-driving positions of the automatic transmission 24 in which the automatic transmission 24 is unable to transmit driving force from each of the driving force sources (engine 12, electric motor MG). The R position and D position of the automatic transmission 24 are driving positions of the automatic transmission 24 in which the automatic transmission 24 is able to transmit driving force from each of the driving force sources.

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

The electronic control device 90 is equipped with a hybrid control means, i.e., a hybrid control unit 92, and a gear shift control means, i.e., a gear shift control unit 94, in order to realize various controls in the vehicle 10.

The hybrid control unit 92 includes a function as an engine control means, i.e., an engine control unit 92a, that controls the operation of the engine 12, a function as 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 a backlash eliminating control unit 92c, which serves as a backlash eliminating control means that executes the backlash eliminating control described below, and executes hybrid drive control using the engine 12 and the electric motor MG, etc., through these control functions.

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

The hybrid control unit 92 outputs an engine control command signal Se for controlling the engine 12 and an MG control command 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 power Win and dischargeable power Wout of the battery 54, etc. The engine control command signal Se is, for example, a command value for the engine power Pe, which is the power of the engine 12 that outputs the engine torque Te at the current engine rotation speed Ne. The MG control command signal Sm is, for example, a command value for the power consumption Wm of the electric motor MG that outputs the MG torque Tm at the current MG rotation speed Nm.

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 unit 90, for example, based on the battery temperature THbat and the state of charge value SOC [%] of the battery 54. The state of charge value SOC of the battery 54 is a value indicating the state of charge corresponding to the amount of charge of the battery 54, and is calculated by the electronic control unit 90, for example, based on the battery charge/discharge current Ibat and the battery voltage Vbat.

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 driving mode to the motor driving (=EV driving) mode. The EV driving mode is a driving mode in which the vehicle can run on driving force from the electric motor MG with the operation of the engine 12 stopped. In the EV driving mode, the hybrid control unit 92 performs EV driving in which the vehicle runs on driving force output only from the electric motor MG, one of the driving force sources (engine 12, electric motor MG), with the K0 clutch 20 in the released state.

On the other hand, when the required drive torque Trdem cannot be met without using at least the output of the engine 12, the hybrid control unit 92 sets the driving mode to the engine driving mode, i.e., hybrid driving (= HV driving) mode. In the HV driving mode, the hybrid control unit 92 performs engine driving, i.e., HV driving, in which driving force is output from at least the engine 12 of the driving force sources (engine 12, electric motor MG) when the K0 clutch 20 is engaged. On the other hand, even if the required drive torque Trdem can be met 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 is less than a predetermined engine start threshold value or when the engine 12, etc., needs to be warmed up. 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 it is necessary to forcibly start the engine 12 and charge the battery 54.

The motor control unit 92b executes MG idling control, which is idling control of the motor MG, for example, when the engine 12 is stopped. The MG idling control is a control for controlling the MG rotation speed Nm to an MG idle rotation speed, which is an idling rotation speed of the motor MG that is equal to or higher than a predetermined rotation speed Nmf, to put the motor MG in an idling state. The MG idling control is a control for outputting a predetermined torque from the motor MG to cause a creep phenomenon in which the vehicle 10 moves slowly with the accelerator off when the brake is off during a temporary stop, for example, when the engine 12 is stopped and the accelerator is off. The predetermined torque is, for example, a creep torque Tcr for running the vehicle 10 in a so-called creep running mode when the brake is off and the accelerator is off in a vehicle stopped state. The MG idling control by the electric motor control unit 92b is executed, for example, in the EV driving mode, when the drive demand amount is equal to or less than a predetermined zero determination threshold at which it can be determined that the drive demand amount is zero, and the shift lever 64 is in the D operating position or the R operating position. When the drive demand amount is equal to or less than the zero determination threshold, it is, for example, when the accelerator opening θacc is determined to be zero and the accelerator is off.

The shift control unit 94 uses, for example, a shift map, which is a predetermined relationship, to determine whether to shift the automatic transmission 24, and outputs a CB hydraulic control command signal Scb to the hydraulic control circuit 56 to execute shift control of the automatic transmission 24 as necessary. In the shift control of the automatic transmission 24, the shift control unit 94 performs shifting of the automatic transmission 24, for example, by switching the disengagement side engagement device to a disengaged state and switching the engagement side engagement device to an engaged state. The shift map is a predetermined relationship having a shift line for determining whether to shift the automatic transmission 24, for example, on a two-dimensional coordinate system with the vehicle speed V and the required driving torque Trdem as variables. In the shift map, the AT output rotation 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.

The shift control unit 94 includes a function as a garage control means, i.e., a garage control unit 94a, that performs garage control CTg when a garage operation OPg is performed by the driver. The garage operation OPg is one of the operations of the shift lever 64 by the driver, and is, for example, a predetermined switching operation from a state in which another shift position different from one driving position of the automatic transmission 24 is selected to a state in which that one driving position is selected. When one driving position of the automatic transmission 24 is set to the D position of the automatic transmission 24, the other shift position is, for example, the R position of the automatic transmission 24, which is the other driving position of the automatic transmission 24. In this case, the state in which one driving position of the automatic transmission 24 is selected is a state in which the operating position POSop is set to the D operating position. The state in which the other driving position of the automatic transmission 24 is selected is a state in which the operating position POSop is set to the R operating position. In other words, the garage operation OPg is, for example, an R → D operation. Alternatively, the other shift position may be, for example, the P position or N position of the automatic transmission 24, which is a non-driving position of the automatic transmission 24. In this case, the state in which the non-driving position of the automatic transmission 24 is selected is a state in which the operating position POSop is set to the P operating position or the N operating position. In other words, the garage operation OPg is, for example, an N(P)→D operation. Note that a D→R operation, which is a switching operation from a state in which the D position of the automatic transmission 24 is selected to a state in which the R position is selected, and an N(P)→R operation, which is a switching operation from a state in which the P position or the N position of the automatic transmission 24 is selected to a state in which the R position is selected, are also types of garage operation OPg. Also, depending on the operating position POSop of the shift lever 64, for example, an R→D operation or a D→R operation may go through the N operating position.

In the automatic transmission 24, for example, when the first engagement device CB1 and the third engagement device CB3 of the engagement devices CB are both engaged, a forward gear stage, for example, first gear stage, is formed and the automatic transmission 24 is in the D position. In addition, in the automatic transmission 24, for example, when the second engagement device CB2 and the third engagement device CB3 of the engagement devices CB are both engaged, a reverse gear stage is formed and the automatic transmission 24 is in the R position.

When the driver performs a D→N (P) operation, which is a switching operation from the D position of the automatic transmission 24 to a state where the P position or N position is selected, while the first gear stage is formed, the garage control unit 94a switches the first engagement device CB1 to a disengaged state, for example, to place the automatic transmission 24 in a neutral state. As a result, the automatic transmission 24 is in the P position or the N position. When the driver performs an N (P)→D operation while the automatic transmission 24 is in a neutral state due to the first engagement device CB1 being disengaged as described above, the garage control unit 94a performs garage control CTg, which switches the first engagement device CB1 to an engaged state to form the first gear stage. As a result, the automatic transmission 24 is in the D position.

In addition, when the driver performs an R→N (P) operation, which is a switching operation from a state in which the automatic transmission 24 is in the R position to a state in which the automatic transmission 24 is in the P position or the N position, while the reverse gear stage is formed, the garage control unit 94a switches the second engagement device CB2 to a disengaged state, for example, to place the automatic transmission 24 in a neutral state. As a result, the automatic transmission 24 is in the P position or the N position. When the driver performs an N (P)→R operation while the automatic transmission 24 is in the neutral state due to the second engagement device CB2 being in the disengaged state, the garage control unit 94a performs garage control CTg, which switches the second engagement device CB2 to an engaged state to form a reverse gear stage. As a result, the automatic transmission 24 is in the R position.

In addition, when the driver performs a D→R operation while the first gear stage is formed, the garage control unit 94a performs garage control CTg, for example, by switching the first engagement device CB1 to a disengaged state and switching the second engagement device CB2 to an engaged state to form a gear stage for reverse. This causes the automatic transmission 24 to switch from the D position to the R position. In addition, when the driver performs a R→D operation while the first gear stage is formed, the garage control unit 94a performs garage control CTg, for example, by switching the second engagement device CB2 to a disengaged state and switching the first engagement device CB1 to an engaged state to form a gear stage for reverse. This causes the automatic transmission 24 to switch from the R position to the D position.

The automatic transmission 24 is a mechanical transmission device that has a first engagement device CB1, and when the first engagement device CB1 is engaged, the D position, which is the driving position, is formed as the shift position. Of the engagement devices CB, the first engagement device CB1 involved in forming the D position of the automatic transmission 24 is a predetermined engagement device. In other words, when the first engagement device CB1 is engaged, the automatic transmission 24 is in a driving position that allows the transmission of driving force from the electric motor MG.

The R position, which is given as an example of another shift position for the D position of the automatic transmission 24, is a driving position that is formed when the second engagement device CB2 of the automatic transmission 24 is engaged. Of the engagement devices CB, the second engagement device CB2 involved in forming the R position of the automatic transmission 24 is a specified engagement device. In other words, when the second engagement device CB2 is engaged, the automatic transmission 24 is in a driving position that allows the transmission of driving force from the electric motor MG.

Here, in order to suppress engagement shock, the garage control unit 94a outputs a CB hydraulic control command signal Scb to the hydraulic control circuit 56 to execute a loose engagement command DRls that gradually increases the command pressure of a specific engagement device, which is an engagement device engaged in the garage control CTg, to gently engage the specific engagement device. In other words, the garage control unit 94a executes normal garage control CTgn that executes a loose engagement command DRls. The loose engagement command DRls is an engagement command that gently engages the specific engagement device compared to the sudden engagement command DRhs described later.

Alternatively, in order to execute garage control CTg more quickly than normal garage control CTgn, garage control unit 94a may execute a sudden engagement command DRhs, which increases the command pressure of a predetermined engagement device in a stepwise manner, instead of a loose engagement command DRls, to quickly engage the predetermined engagement device. However, if a sudden engagement command DRhs is executed when torque is input to automatic transmission 24, an engagement shock may easily occur, or the predetermined engagement device may not be quickly engaged even if a sudden engagement command DRhs is executed. It is desirable to execute the sudden engagement command DRhs when torque is not input to automatic transmission 24. A state in which torque does not need to be input to automatic transmission 24 is, for example, when the accelerator is off, and when the output of creep torque Tcr may be temporarily stopped. When the output of creep torque Tcr may be temporarily stopped, the state is EV driving mode, taking responsiveness into consideration.

When the garage control unit 94a performs a garage operation OPg by the driver, the garage control unit 94a performs a sudden engagement command DRhs in a state in which the output of the creep torque Tcr is stopped, i.e., in a creep cut state, and then executes a rapid garage control CTgq, which increases the MG rotation speed Nm to a predetermined rotation speed Nmf or higher and causes the electric motor MG to output an MG torque Tm equivalent to the creep torque Tcr. The creep cut state is a state in which the output of the creep torque Tcr is prohibited and the MG rotation speed Nm is set to zero. The garage control unit 94a executes the rapid garage control CTgq when the garage operation OPg is performed by the driver in the EV driving mode in which the operation of the engine 12 is stopped. Since the sudden engagement command DRhs is executed with the MG rotation speed Nm set to zero, the garage control unit 94a drives the EOP 60 while the quick garage control CTgq is being executed, and controls the CB hydraulic pressure PRcb, which is the engagement hydraulic pressure of the specified engagement device, as the original pressure of the hydraulic oil OIL discharged from the EOP 60. Note that if the MOP 58 is connected to a rotating member other than the pump impeller 22a and the other rotating member is rotating while the vehicle 10 is traveling in the EV driving mode, the EOP 60 does not need to be operated.

Whether or not to execute the above-mentioned quick garage control CTgq is determined based on whether or not each of the following predetermined conditions is satisfied: the EV driving mode, the accelerator is off, the AT input rotation speed Ni, i.e., the turbine rotation speed Nt, is equal to or lower than a predetermined input rotation speed Nif, and the AT output rotation speed No is equal to or lower than a predetermined rotation speed Nof. Note that the predetermined input rotation speed Nif and the predetermined rotation speed Nof are both set to zero or close to zero.

In addition, in the transitional period in which the MG rotation speed Nm is increased in the rapid garage control CTgq, when the rotation of the electric motor MG is transmitted to the automatic transmission 24, the backlash formed on the power transmission path of the automatic transmission 24 is eliminated (backlash elimination). The backlash is a gap formed between gears that are provided on the power transmission path of the automatic transmission 24 and mesh with each other. At this time, when the backlash is eliminated, there is a risk of a shock being generated due to the impact of the gears colliding with each other. In order to suppress the shock caused by this backlash elimination, the garage control unit 94a outputs an output command DRop to the backlash elimination control unit 92c to execute the backlash elimination control CTp. Upon receiving the output command DRop from the garage control unit 94a, the backlash elimination control unit 92c executes the backlash elimination control CTp to control the MG rotation speed Nm during the transitional period in which the MG rotation speed Nm is increased, so as to reduce the shock generated when the backlash formed on the power transmission path is eliminated.

When the backlash elimination control unit 92c receives an output command DRop to execute the backlash elimination control CTp, it starts increasing the MG rotation speed Nm from the time when a predetermined time TMf has elapsed since the time when the sudden engagement command DRhs was output in the creep cut state, and increases the MG rotation speed Nm at a predetermined increasing gradient. In addition, when the MG rotation speed Nm reaches a predetermined rotation speed, the backlash elimination control unit 92c maintains the MG rotation speed at that predetermined rotation speed for a predetermined time. The predetermined increasing gradient of the MG rotation speed Nm by the backlash elimination control CTp, the predetermined rotation speed at which the MG rotation speed Nm is maintained, and the predetermined time for which the MG rotation speed Nm is maintained at the predetermined rotation speed are determined in advance experimentally or by design, and are set to threshold values at which the shock caused by backlash elimination occurring during the rising transition period of the MG rotation speed Nm is within an acceptable range and the execution time of the backlash elimination control CTp is minimized. The predetermined time TMf is, for example, the time when it can be determined that the switching of the predetermined engagement device engaged in the garage control CTg to the engaged state has progressed, that is, the time when the torque capacity of the predetermined engagement device becomes the capacity capable of transmitting the MG torque Tm of the electric motor MG. In this way, by temporarily maintaining the MG rotation speed Nm at the predetermined rotation speed during the rising transition period of the MG rotation speed Nm, the impact caused by the collision of the gears when the backlash is eliminated is reduced, and the shock is reduced. When the backlash elimination control CTp is completed, the electric motor control unit 92b increases the MG rotation speed Nm to the predetermined rotation speed Nmf or more, and then outputs the MG torque Tm equivalent to the creep torque Tcr from the electric motor MG. Hereinafter, for convenience, the output of the MG torque Tm equivalent to the creep torque Tcr from the electric motor MG is described as the output of the creep torque Tcr from the electric motor MG.

When the garage operation OPg is, for example, an R→D operation, it is necessary to switch the second engagement device CB2 to a released state. In addition, in the R position, the creep torque Tcr is output from the electric motor MG. When the garage operation OPg, which is an R→D operation, is performed by the driver, the garage control unit 94a outputs a CB hydraulic control command signal Scb to the hydraulic control circuit 56 to perform a release command DRr to release the second engagement device CB2 by reducing the command pressure of the second engagement device CB2 before starting a rapid engagement command DRhs for the first engagement device CB1. In addition, when the garage operation OPg is performed by the driver while the creep torque Tcr is being output from the electric motor MG, the garage control unit 94a executes rapid garage control CTgq with the output of the creep torque Tcr temporarily stopped.

After the start of the rapid garage control CTgq, the driver may release the brake pedal and operate the accelerator in order to quickly accelerate the vehicle 10. At this time, if the MG torque Tm is output from the electric motor MG after waiting for the MG rotation speed Nm of the electric motor MG to increase through the backlash elimination control CTp, the time delay between the time the accelerator is operated and the time the MG torque Tm is output will be large (reduced responsiveness), which may cause the driver to feel uncomfortable. On the other hand, if the MG rotation speed Nm is increased at the time the accelerator is operated to output the MG torque Tm from the electric motor MG, the first engagement device CB1 will be rapidly engaged while the MG torque Tm is being output, which may cause a shock.

On the other hand, when the accelerator is operated during the execution of the rapid garage control CTgq, particularly when the driver operates the accelerator before the backlash-reducing control CTp is started, the garage control unit 94a causes the garage control unit 94a to continue the rapid garage control CTgq until the MG rotation speed Nm of the electric motor MG starts to increase. In other words, the rapid garage control CTgq is controlled so that it is not interrupted by the accelerator operation by the driver. On the other hand, when the accelerator is operated during the execution of the rapid garage control CTgq, the garage control unit 94a outputs an output command DRop to the electric motor control unit 92b to increase the MG rotation speed Nm without executing the backlash-reducing control CTp during the increasing transition period of the MG rotation speed Nm of the electric motor MG. Based on the output command DRop from the garage control unit 94a, the electric motor control unit 92b increases the MG rotation speed Nm to a predetermined rotation speed Nmf or higher without executing the backlash eliminating control CTp, and generates an MG torque Tm from the electric motor MG according to the accelerator opening θacc.

In this way, even if the accelerator is operated before the backlash-eliminating control CTp begins, the rapid garage control CTgq continues and the MG rotation speed Nm is controlled to zero, i.e., the MG torque Tm is controlled to zero, thereby suppressing shock caused by the first engagement device CB1 being suddenly engaged while the MG torque Tm is being output from the electric motor MG. In addition, the MG rotation speed Nm is increased after the sudden engagement command DRhs for the first engagement device CB1 is output, but at this time, because the backlash-eliminating control CTp is not executed during the increasing transition period of the MG rotation speed Nm, the MG rotation speed Nm increases quickly by that amount, and the MG torque Tm is quickly output. As a result, the torque responsiveness to the accelerator operation is accelerated.

In addition, when the accelerator is operated during the execution of the rapid garage control CTgq, the garage control unit 94a can also determine whether or not to execute the backlash eliminating control CTp based on the accelerator opening θacc, which is the accelerator operation amount (i.e., the accelerator pedal depression amount). Specifically, the garage control unit 94a determines not to execute the backlash eliminating control CTp when the accelerator opening θacc is equal to or greater than the predetermined opening ACL, and determines to execute the backlash eliminating control CTp when the accelerator opening θacc is less than the predetermined opening ACL. Therefore, when the accelerator opening θacc is equal to or greater than the predetermined opening ACL, the garage control unit 94a outputs an output command DRop to the motor control unit 92b to increase the MG rotation speed Nm without executing the backlash eliminating control CTp and generate the MG torque Tm according to the accelerator opening θacc from the electric motor MG. On the other hand, when the accelerator opening θacc is less than the predetermined opening ACL, the garage control unit 94a executes the backlash eliminating control CTp, and then outputs an output command DRop to the backlash eliminating control unit 92c and the electric motor control unit 92b to generate a creep torque Tcr from the electric motor MG.

The predetermined opening ACL of the accelerator opening θacc is determined in advance experimentally or by design, and is set as a threshold value of the accelerator opening θacc at which the driver can determine that he or she wants to prioritize quick acceleration over shocks caused by backlash elimination. Therefore, when the accelerator opening θacc is equal to or greater than the predetermined opening ACL and the driver can determine that he or she wants to prioritize quick acceleration, the MG rotation speed Nm is increased and the MG torque Tm is quickly output from the motor MG without executing the backlash elimination control CTp by the motor MG. Also, when the accelerator opening θacc is less than the predetermined opening ACL and the driver cannot determine that quick acceleration is prioritized, the backlash elimination control CTp is executed to temporarily hold the MG rotation speed Nm of the motor MG. As a result, the shocks caused by backlash elimination are reduced. In this way, by determining whether or not to execute the backlash elimination control CTp according to the accelerator opening θacc, it is possible to preferably achieve both suppression of shocks caused by backlash elimination and acceleration responsiveness.

In addition, from another perspective in determining the predetermined opening ACL of the accelerator opening θacc, the driver's sensitivity to shocks during acceleration decreases as the accelerator opening θacc increases. Therefore, the predetermined opening ACL is set to a threshold value of the accelerator opening θacc at which the driver hardly feels any shocks that occur during acceleration.

The hybrid control unit 92 determines whether the driving mode is EV driving mode.

The garage control unit 94a determines whether or not a garage operation OPg has been performed by the driver. When the hybrid control unit 92 determines that the driving mode is the EV driving mode and the garage control unit 94a determines that a garage operation OPg has been performed by the driver, if there is a release side engagement device that can be switched to a released state in the garage control CTg, the garage control unit 94a outputs a CB hydraulic control command signal Scb to the hydraulic control circuit 56 to issue a release command DRr to release the release side engagement device.

When the hybrid control unit 92 determines that the driving mode is the EV driving mode, and determines that the garage operation OPg has been performed by the driver, the garage control unit 94a determines whether or not the predetermined conditions for executing the above-mentioned rapid garage control CTgq are satisfied. When the garage control unit 94a determines that the predetermined conditions are satisfied and creep torque Tcr is being output, it outputs an output stop command DRst to stop the output of creep torque Tcr. The electric motor control unit 92b stops the output of creep torque Tcr from the electric motor MG based on the output stop command DRst.

When the hybrid control unit 92 determines that the driving mode is the EV driving mode, the garage control unit 94a determines that the garage operation OPg has been performed by the driver, and if it further determines that the above-mentioned predetermined conditions are satisfied, it determines whether or not the creep cut state is in effect. The garage control unit 94a determines whether or not the creep cut state is in effect, for example, based on whether or not the MG rotation speed Nm is zero or a very small rotation speed close to zero.

When the garage control unit 94a determines that the creep cut state is in effect, it outputs a CB hydraulic control command signal Scb to the hydraulic control circuit 56 to issue a sudden engagement command DRhs to quickly engage the first engagement device CB1, i.e., the engagement side engagement device, which is switched to the engaged state in the garage control CTg.

When the garage control unit 94a outputs the sudden engagement command DRhs, it judges whether the accelerator opening θacc is equal to or greater than the predetermined opening ACL. If the accelerator opening θacc is equal to or greater than the predetermined opening ACL, the garage control unit 94a outputs an output command DRop to quickly increase the MG rotation speed Nm to a predetermined rotation speed Nmf or higher and output the MG torque Tm based on the accelerator opening θacc after a predetermined time TMf has elapsed since the time when the CB hydraulic control command signal Scb for executing the sudden engagement command DRhs was output, during which it can be determined that the switching of the engaging side engagement device to the engaged state in the garage control CTg has progressed. The electric motor control unit 92b quickly increases the MG rotation speed Nm based on the output command DRop, and outputs the MG torque Tm according to the accelerator opening θacc from the electric motor MG.

On the other hand, when the accelerator opening θacc is less than the predetermined opening ACL, the garage control unit 94a outputs an output command DRop to execute the backlash elimination control CTp by the electric motor MG after a predetermined time TMf has elapsed since the time when the CB hydraulic control command signal Scb for executing the sudden engagement command DRhs was output. The backlash elimination control unit 92c executes the backlash elimination control CTp by the electric motor MG based on the output command DRop, and when the backlash elimination control CTp is completed, the electric motor control unit 92b increases the MG rotation speed Nm and causes the electric motor MG to output the MG torque Tm according to the accelerator opening θacc.

Figure 2 is a flowchart that explains the main control operations of the electronic control unit 90, and is a flowchart that explains the control operations when the driver operates the accelerator after garage operation OPg. This flowchart is executed repeatedly while the vehicle 10 is being driven.

2, first, in step S10 (hereinafter, step will be omitted) corresponding to the control function of the hybrid control unit 92, it is determined whether the driving mode is the EV driving mode. If the determination in S10 is negative, this routine is terminated. If the determination in S10 is positive, in S20 corresponding to the control function of the garage control unit 94a, it is determined whether the garage operation OPg has been performed by the driver. If the determination in S20 is negative, this routine is terminated. If the determination in S20 is positive, in S30 corresponding to the control function of the garage control unit 94a, it is determined whether a predetermined condition for executing the rapid garage control CTgq is satisfied. If the determination in S30 is negative, in S40 corresponding to the control function of the garage control unit 94a, if there is a release side engagement device in the garage control CTg, a release command DRr for releasing the release side engagement device is output. Next, in S50, which corresponds to the control function of the garage control unit 94a, a loose engagement command DRls is output to loosely engage the engagement side engagement device in the garage control CTg.

If the judgment in S30 is positive, in S60 corresponding to the control functions of the garage control unit 94a and the electric motor control unit 92b, if the creep torque Tcr is being output from the electric motor MG, the output of the creep torque Tcr is stopped. Next, in S70 corresponding to the control function of the garage control unit 94a, if there is a release side engagement device in the garage control CTg, a release command DRr is output to release the release side engagement device. Next, in S80 corresponding to the control function of the garage control unit 94a, it is judged whether or not the creep cut state is in effect. If the judgment in S80 is negative, S80 is executed repeatedly. If the judgment in S80 is positive, in S90 corresponding to the control function of the garage control unit 94a, a sudden engagement command DRhs is output to quickly engage the engagement side engagement device in the garage control CTg, and the engagement side engagement device is quickly engaged.

Next, in S100, which corresponds to the control function of the garage control unit 94a, it is determined whether the accelerator opening θacc is equal to or greater than the predetermined opening ACL. If the determination in S100 is positive, in S120, which corresponds to the control functions of the garage control unit 94a and the electric motor control unit 92b, the MG rotation speed Nm is quickly increased to or greater than the predetermined rotation speed Nmf after a predetermined time TMf has elapsed since the output of the sudden engagement command DRhs, and the MG torque Tm corresponding to the accelerator opening θacc is output from the electric motor MG. If the determination in S100 is negative, in S110, which corresponds to the control function of the backlash-eliminating control unit 92c, the backlash-eliminating control CTp by the electric motor MG is started after a predetermined time TMf has elapsed since the output of the sudden engagement command DRhs. When the backlash eliminating control CTp is completed, in S120, which corresponds to the control functions of the garage control unit 94a and the electric motor control unit 92b, the MG rotation speed Nm is increased to a predetermined rotation speed Nmf or higher, and the electric motor MG outputs the MG torque Tm according to the creep torque Tcr or the accelerator opening θacc. Based on the flowchart in FIG. 2, the rapid garage control CTgq continues regardless of the presence or absence of accelerator operation until the backlash eliminating control CTp is started, and the presence or absence of execution of the backlash eliminating control CTp by the electric motor MG thereafter is determined based on the accelerator opening θacc, which is the amount of accelerator operation. Therefore, by appropriately determining whether or not to execute the backlash eliminating control CTp based on the accelerator opening θacc, it is possible to suppress shocks and ensure responsiveness to accelerator operation at the same time.

Figure 3 is a diagram showing an example of a case where the driver performs an R→D operation when creep torque Tcr is output in the R position of the automatic transmission 24 in the EV mode. In Figure 3, time t1 corresponds to the time when garage control CTg is started in response to the driver performing the R→D operation. In the garage control CTg, a shift control is executed to switch the automatic transmission 24 from the R position to the D position, that is, to release the second engagement device CB2, which is the release side engagement device, and to engage the first engagement device CB1, which is the engagement side engagement device. In Figure 3, the release side hydraulic pressure indicates the CB hydraulic pressure PRcb of the second engagement device CB2, which is the release side engagement device. The engagement side hydraulic pressure indicates the CB hydraulic pressure PRcb of the first engagement device CB1, which is the engagement side engagement device. In each of the release side hydraulic pressure and the engagement side hydraulic pressure, the actual value indicated by the solid line is the actual pressure, and the indicated value indicated by the dashed line is the indicated pressure. Here, FIG. 3 shows a state in which a predetermined condition for executing quick garage control CTgq is met at the start of garage control CTg, and quick garage control CTgq is executed.

At time t1, the rapid garage control CTgq is started and the second engagement device CB2 is released. Also, since the predetermined conditions for executing the rapid garage control CTgq are met at time t1, the MG rotation speed Nm is reduced toward zero and transitions to the creep cut state. When the MG rotation speed Nm becomes zero at time t2 and the creep cut state is entered, a rapid engagement command DRhs is output to quickly engage the first engagement device CB1, and the command pressure of the engagement side hydraulic pressure increases in a stepped manner to the maximum pressure at which the first engagement device CB1 is fully engaged, as shown by the dashed line. As a result, the actual pressure of the engagement side hydraulic pressure, shown by the solid line, increases at a relatively high change gradient with a delay relative to the command pressure. At time t3, a predetermined time TMf after time t2, the creep cut state is released and the MG rotation speed Nm begins to increase.

Here, the MG rotation speed Nm shown by the solid line from time t3 onwards corresponds to the rotation speed when the accelerator opening θacc is equal to or greater than the predetermined opening ACL. When the accelerator opening θacc is equal to or greater than the predetermined opening ACL, the MG rotation speed Nm is quickly increased to equal to or greater than the predetermined rotation speed Nmf as shown by the solid line, and the MG torque Tm according to the accelerator opening θacc is output from the electric motor MG. As a result, when the accelerator opening θacc is equal to or greater than the predetermined opening ACL, the MG rotation speed Nm is quickly increased and the MG torque Tm is output, completing garage control at time t4a.

The MG rotation speed Nm shown by the dashed line after time t3 corresponds to the rotation speed when the accelerator opening θacc is less than the predetermined opening ACL. When the accelerator opening θacc is less than the predetermined opening ACL, the MG rotation speed Nm rises to a predetermined rotation speed at a lower rising gradient than the MG rotation speed Nm shown by the solid line, and then the backlash-eliminating control CTp is executed to temporarily hold the MG rotation speed at that predetermined rotation speed for a predetermined time. At time tg when the backlash-eliminating control CTp is completed, the MG rotation speed Nm further rises and the creep torque Tcr is output from the electric motor MG. As a result, when the accelerator opening θacc is less than the predetermined opening ACL, the backlash-eliminating control CTp is executed while the MG rotation speed Nm is rising, and the garage control is completed at time t4b. In this way, when the accelerator opening θacc is equal to or greater than the predetermined opening ACL, the garage control is completed sooner, and the torque is output from the drive wheels 14 sooner, resulting in appropriate acceleration response. On the other hand, when the accelerator opening θacc is less than the predetermined opening ACL, the garage control is completed later than at time t4b and time t4a, but the occurrence of shock is reduced by the backlash elimination control CTp.

As described above, according to this embodiment, even if the driver operates the accelerator while the rapid garage control CTgq is being executed and before the backlash eliminating control CTp is started, the rapid garage control CTgq continues, suppressing shocks caused by interrupting the rapid garage control CTgq. On the other hand, the MG rotation speed Nm of the electric motor MG is increased without executing the backlash eliminating control CTp executed during the transitional period in which the MG rotation speed Nm of the electric motor MG is increased, so that the responsiveness to the accelerator operation can be increased accordingly. This makes it possible to achieve both suppression of shocks that occur during switching operations and responsiveness to the accelerator operation.

In addition, according to this embodiment, when the accelerator opening θacc is equal to or greater than the predetermined opening ACL, the MG rotation speed Nm of the electric motor MG is increased without executing the backlash eliminating control CTp. Therefore, when the accelerator opening θacc is less than the predetermined opening ACL, the backlash eliminating control CTp is executed during the rising transition period of the MG rotation speed Nm of the electric motor MG. As a result, by appropriately setting the predetermined opening ACL for the accelerator opening θacc, for example, when the accelerator opening θacc is small, the backlash eliminating control CTp can be executed with priority given to suppressing shock. In addition, when a predetermined switching operation is performed in the motor driving mode in which the vehicle can run with the driving force from the electric motor MG while the engine 12 is stopped, the rapid garage control CTgq is executed, so that the rapid garage control CTgq is appropriately executed when a predetermined torque that causes a creep phenomenon is output from the electric motor MG. In addition, when a predetermined switching operation is performed while a predetermined torque is being output from the electric motor MG, the rapid garage control CTgq is executed in a state where the predetermined torque is temporarily stopped, so that the rapid garage control CTgq can be executed appropriately. In addition, by driving the EOP 60 while the rapid garage control CTgq is being executed, the hydraulic pressure of the hydraulic oil OIL discharged from the EOP 60 can be used as the source pressure to realize the command pressure of the engagement side engagement device.

The above describes in detail an embodiment of the present invention based on the drawings, but the present invention can also be applied in other aspects.

For example, in the flowchart shown in FIG. 2 of the above embodiment, the order of each step may be changed as appropriate within the scope of no inconsistency. For example, in FIG. 2, when the driver performs a garage operation, a step (S30) is executed to determine whether or not to execute rapid garage control CTgq based on whether or not a predetermined condition is satisfied, but between S20 and S30, steps (S40, S70) may be executed to output a release command if there is a release side engagement device.

In addition, in the above embodiment, the first engagement device CB1 involved in forming the D position of the automatic transmission 24 among the engagement devices CB is exemplified as the predetermined engagement device, and garage operation OPg to the D operating position is exemplified, but this is not limited to the embodiment. For example, the present invention can also be applied to garage operation OPg to the R operating position, in which the second engagement device CB2 involved in forming the R position of the automatic transmission 24 is the predetermined engagement device.

In the above embodiment, the vehicle to which the present invention is applied is exemplified as a vehicle 10 equipped with an engine 12, an electric motor MG, and an automatic transmission 24, but the present invention is not limited to this embodiment. For example, the present invention can be applied to an electric vehicle that does not have an engine and uses only an electric motor as a driving force source, or a hybrid vehicle that has an automatic transmission in series after a known electric continuously variable transmission. In addition, if the vehicle is, for example, the electric vehicle, the automatic transmission that transmits the driving force from the electric motor may be replaced with a mechanical transmission device that simply has an engagement device. In short, the present invention can be applied to any vehicle that has an electric motor and a mechanical transmission device that has a predetermined engagement device and in which a driving position that allows the transmission of driving force from the electric motor by engaging the predetermined engagement device is formed as a shift position.

In addition, in the above embodiment, a planetary gear type automatic transmission is exemplified as the automatic transmission 24, but this is not limited to the embodiment. For example, the automatic transmission 24 may be a known DCT (Dual Clutch Transmission), a known belt type continuously variable transmission, etc. When the automatic transmission 24 is a DCT, one of the engagement devices connected to each of the input shafts of the two systems corresponds to the specified engagement device. When the automatic transmission 24 is a belt type continuously variable transmission, one of the engagement devices of the forward clutch and the reverse brake of a known forward/reverse switching device provided together with the belt type continuously variable transmission corresponds to the specified engagement device.

In addition, in the above embodiment, the torque converter 22 is used as the fluid transmission device, but this is not limited to the embodiment. For example, instead of the torque converter 22, other fluid transmission devices such as a fluid coupling that does not have a torque amplifying effect may be used as the fluid transmission device. Alternatively, the fluid transmission device does not necessarily have to be provided, and may be replaced with, for example, a clutch for starting.

Note that the above is merely one embodiment, and the present invention can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art.

10: vehicle 12: engine 24: automatic transmission (mechanical transmission device)
60: EOP (electric oil pump)
90: Electronic control device (control device)
92b: Electric motor control unit 92c: Backlash reduction control unit 94a: Garage control unit CB1: First engagement device (predetermined engagement device)
CB2: Second engagement device (predetermined engagement device)
MG: Electric motor

Claims (5)

A control device for a vehicle including an electric motor and a mechanical transmission device having a predetermined engagement device, the predetermined engagement device being brought into an engaged state to form a driving position that allows transmission of driving force from the electric motor as a shift position,
an electric motor control unit that controls a rotation speed of the electric motor to be equal to or higher than a predetermined rotation speed and causes the electric motor to output a predetermined torque that causes a creep phenomenon;
a garage control unit that, when a predetermined switching operation is performed by a driver from a state in which a different shift position different from the driving position of the mechanical transmission device is selected to a state in which the driving position is selected, performs control to quickly engage the predetermined engagement device by stepwise increasing a command pressure of the predetermined engagement device in a state in which the output of the predetermined torque is stopped, and then executes rapid garage control to increase the rotation speed of the electric motor to or above the predetermined rotation speed;
and a backlash eliminating control unit that executes backlash eliminating control to control the rotation speed of the electric motor so as to reduce a shock that occurs when backlash formed on a power transmission path of the mechanical transmission device is eliminated during a transitional period in which the garage control unit increases the rotation speed of the electric motor,
A vehicle control device characterized in that, when the driver operates the accelerator while the quick garage control is being executed and before the backlash elimination control is started, the garage control unit continues the quick garage control until the rotational speed of the electric motor starts to increase, and increases the rotational speed of the electric motor to above the predetermined rotational speed during a transitional period in which the rotational speed of the electric motor is increased without executing the backlash elimination control. 2. The vehicle control device according to claim 1, wherein the garage control unit increases the rotation speed of the electric motor to or above the predetermined rotation speed without executing the backlash elimination control when the amount of operation of the accelerator is equal to or greater than a predetermined amount. The vehicle control device according to claim 1 or 2, characterized in that the garage control unit executes the rapid garage control when the driver performs the specified switching operation in a motor driving mode in which the vehicle can run using driving force from the electric motor with the operation of the engine of the vehicle stopped. 4. The vehicle control device according to claim 1, wherein when the driver performs the predetermined switching operation while the predetermined torque is being output from the electric motor, the garage control unit executes the rapid garage control in a state where the output of the predetermined torque is temporarily stopped. 5. The vehicle control device according to claim 1, wherein the garage control unit drives an electric oil pump provided in the vehicle while the quick garage control is being executed, and controls the engagement oil pressure of the predetermined engagement device using the hydraulic pressure of the hydraulic oil discharged from the electric oil pump as a base pressure.

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