JP2009262659A - Starting controller for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow starting without imparting an incongruity sense to a driver in time of failure of an electric sub-oil pump. <P>SOLUTION: This starting controller for a hybrid vehicle is provided with a starting control means raising, to a value exceeding a prescribed value, a rotation speed of a main oil pump by at least one of an engine and a motor/generator such that a prescribed line pressure can be secured (step S5) with a transmission side friction element opening-instructed (step S4) when a starting request decision means decides that a starting request is given (step S2) when a sub-oil pump failure decision means decides that the electric sub-oil pump has the failure (step S1) and when the rotation speed of the main oil pump is the prescribed value or below (step S3), and generating driving force in driving wheels by torque capacity control of the transmission side friction element after securing the prescribed line pressure. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hybrid vehicle that can be driven not only by an engine but also by power from a motor / generator, and more particularly to a start control device for the hybrid vehicle.

  Conventionally, for example, the drive system of the hybrid vehicle as described above is known. The drive system includes an engine, an automatic transmission having an input shaft drivingly coupled to the output shaft of the engine and an output shaft drivingly coupled to a drive wheel, and an engine transmission shaft and an automatic transmission input shaft. Torque converter for connecting the inserted motor / generator, the first clutch for detachably connecting the engine output shaft and the motor / generator, and the input shaft and the output shaft for the automatic transmission by hydraulic pressure. And a main oil pump that is inserted between the motor / generator and the second clutch and is driven by the motor / generator to supply hydraulic pressure to at least the second clutch. Is.

  When a hybrid vehicle having such a drive system releases the first clutch and engages the second clutch, the hybrid vehicle is in an electric travel (EV) mode that travels only by the power from the motor / generator, and the first clutch and the second clutch. When the two are fastened together, a hybrid running (HEV) mode that can run with power from both the engine and the motor / generator can be set.

  By the way, the hybrid vehicle as described above is a motor / generator for a case where the first and second clutches and the automatic transmission are started when the vehicle is stopped and the main oil pump is not operated. It is usual to have an electric sub oil pump that is driven by a motor other than the motor and supplies hydraulic pressure to them. However, if this electric sub oil pump fails, the hydraulic pressure that can be engaged at least with the second clutch is obtained as it is. It becomes difficult to start after it is lost.

Therefore, for example, Patent Document 2 discloses a technique for securing a predetermined hydraulic pressure by operating a main oil pump by driving a motor / generator at a lower rotational speed than an idle rotation of an engine when an electric sub-oil pump of a hybrid vehicle fails. Proposed.
Japanese Patent Laid-Open No. 11-082260 JP 2003-172165 A

  However, in this conventional configuration, if the second clutch is engaged with the hydraulic pressure until the predetermined hydraulic pressure is ensured, the hydraulic pressure is not sufficiently high, so the second clutch cannot exert the engagement force as the target value. For this reason, the driving wheel cannot generate the driving force intended by the driver, and the driver feels uncomfortable.

  Therefore, the present invention is sufficient to operate the transmission-side friction element corresponding to the second clutch that detachably couples the input shaft and the output shaft of the transmission when the electric sub-oil pump of the hybrid vehicle fails. An object of the present invention is to provide a start control device that secures hydraulic pressure and enables start without causing a driver to feel uncomfortable.

  For this purpose, a start control apparatus for a hybrid vehicle according to the present invention includes an engine, a transmission having an input shaft drivingly coupled to an output shaft of the engine and an output shaft drivingly coupled to a drive wheel, and the engine output. A motor / generator interposed between the shaft and the transmission input shaft, an engine-side friction element detachably coupled between the engine output shaft and the motor / generator, and the motor / generator and the transmission input by hydraulic pressure A transmission-side friction element that releasably couples between the shafts or between the transmission input shaft and the transmission output shaft; and the engine and the motor / A main engine that is driven by at least one of the generators to supply hydraulic pressure to at least the transmission-side friction element. In a hybrid vehicle comprising: a drive system having a power pump; and an electric sub-oil pump that is driven by a motor other than the motor / generator and supplies hydraulic pressure to at least the transmission-side friction element. A start request determining means for determining, a sub oil pump failure determining means for determining whether or not the electric sub oil pump has failed, and the sub oil pump failure determining means determining that the electric sub oil pump has a failure; and When the number of revolutions of the main oil pump is equal to or less than a predetermined value, if the start request determining means determines that there is a start request, at least one of the engine and the motor / generator in a state where the transmission side friction element is instructed to be released The rotational speed of the main oil pump is set to the predetermined value so that a predetermined line pressure can be secured. Raised to obtain, it is characterized in that it comprises a and a start control means for generating a driving force to the driving wheels by the torque capacity control of the transmission side friction element after securing the predetermined line pressure.

  In such a start control device of the present invention, when the sub oil pump failure determination means determines that the electric sub oil pump has a failure and the rotation speed of the main oil pump is equal to or less than a predetermined value, the start request determination means When it is determined that there is a start request, the start control means is configured so that at least one of the engine and the motor / generator can maintain the rotational speed of the main oil pump at a predetermined line pressure in a state in which the transmission side friction element is instructed to be released. Pull up until it exceeds a predetermined value, and after ensuring the predetermined line pressure, drive force is generated in the drive wheels by controlling the torque capacity of the transmission side friction element.

  Therefore, according to the start control device of the present invention, it is possible to generate a sufficient driving force on the driving wheel by controlling the torque capacity of the transmission side friction element using a sufficiently high predetermined line pressure. It is possible to make a start that does not cause a sense of incongruity.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
FIG. 1 shows a power train (drive system) of a front engine / rear wheel drive hybrid vehicle to which an embodiment of the start control device of the present invention is applied, where 1 is an engine and 2 is a drive wheel (rear wheel). .
In the power train of the hybrid vehicle shown in FIG. 1, an automatic transmission 3 is arranged in tandem at the rear of the engine 1 in the longitudinal direction of the vehicle in the same manner as a normal rear wheel drive vehicle. The motor / generator 5 is connected to the shaft 4 that transmits the rotation of the motor to the input shaft 3a of the automatic transmission 3.

The motor / generator 5 acts as a motor or acts as a generator (generator), and is interposed between the engine 1 and the automatic transmission 3.
More specifically, a first clutch 6 as an engine-side friction element is interposed between the motor / generator 5 and the engine 1 and, more specifically, between the shaft 4 and the engine crankshaft 1a. / The generators 5 are connected so as to be separable.
Here, the first clutch 6 is assumed to be capable of continuously changing the transmission torque capacity. For example, the first clutch 6 is a wet type engine that can change the transmission torque capacity by continuously controlling the clutch hydraulic oil flow rate and the clutch hydraulic pressure with a proportional solenoid. It consists of friction elements such as a plate clutch.

More specifically, a second clutch 7 as a transmission side friction element is interposed between the motor / generator 5 and the automatic transmission 3 and more specifically between the shaft 4 and the transmission input shaft 3a. / The generator 5 and the automatic transmission 3 are detachably coupled.
Similarly to the first clutch 6, the second clutch 7 can be continuously changed in transmission torque capacity. For example, the proportional torque solenoid can continuously control the clutch hydraulic oil flow rate and clutch hydraulic pressure to change the transmission torque capacity. Consists of friction elements such as possible wet multi-plate clutch. As the second clutch 7, here, a friction element for selecting a forward shift stage or a friction element for selecting a reverse shift stage existing in the automatic transmission 3 is used.

The automatic transmission 3 determines the transmission system path (shift stage) by selectively engaging and releasing a plurality of friction elements (clutch, brake, etc.) by combining the engagement and release of these friction elements. And
Therefore, the automatic transmission 3 shifts the rotation from the input shaft 3a at a gear ratio corresponding to the selected shift speed and outputs it to the output shaft 3b.
This output rotation is distributed and transmitted to the left and right rear wheels 2 (only the right rear wheel is shown in the figure) by the differential gear device 8 and used for traveling of the vehicle.
However, it is needless to say that the automatic transmission 3 is not limited to the stepped type as described above, and may be a transmission that can be continuously changed from the current shift stage to the target shift stage.

  In the power train of FIG. 1 described above, when the electric travel (EV) mode used at low load and low vehicle speed including when starting from a stopped state is required, the first clutch 6 is released and the second clutch is released. 7 is engaged, and the automatic transmission 3 is brought into a power transmission state.

When the motor / generator 5 is driven in this state, only the output rotation from the motor / generator 5 reaches the transmission input shaft 3a, and the automatic transmission 3 changes the rotation to the input shaft 3a to the selected shift speed. The speed is changed according to the speed and output from the transmission output shaft 3b.
Then, the rotation from the transmission output shaft 3b reaches the rear wheel 2 via the differential gear device 8, and the vehicle can be electrically driven (EV traveling) only by the motor / generator 5.

Requires hybrid driving (HEV driving) mode used for high-speed driving and heavy-duty driving
When this is done, both the first clutch 6 and the second clutch 7 are engaged, and the automatic transmission 3 is brought into a power transmission state.
In this state, the output rotation from the engine 1, or both the output rotation from the engine 1 and the output rotation from the motor / generator 5 reach the transmission input shaft 3a, and the automatic transmission 3 is connected to the input shaft 3a. Is rotated according to the currently selected shift speed and output from the transmission output shaft 3b.
The rotation from the transmission output shaft 3b then reaches the rear wheel 2 via the differential gear device 8, and the vehicle can be hybrid-driven (HEV-driven) by both the engine 1 and the motor / generator 5.

  When the engine 1 is started in the EV travel mode in which the engine 1 is stopped and the first clutch 6 is released and the second clutch 7 is engaged and only the power from the motor / generator 5 is driven, the first clutch 6 is engaged. Crank using the motor / generator 5 as an engine starter. Then, after the engine 1 is started, the mode is switched to the HEV travel mode in which the vehicle travels by power from both the engine 1 and the motor / generator 5.

  In such HEV traveling, if the engine 1 is operated with the optimum fuel efficiency and the energy becomes surplus, the surplus energy is converted into electric power by operating the motor / generator 5 as a generator by this surplus energy, and this generated power is converted into electric power. By accumulating power to be used for driving the motor of the motor / generator 5, the fuel consumption of the engine 1 can be improved.

In order to obtain a predetermined line pressure for operating the automatic transmission 3 and operating the first clutch 6 and the second clutch 7, the main oil pump 9 is inserted between the motor / generator 5 and the second clutch 7 for automatic transmission. It is coupled to the transmission input shaft 3a of the machine 3.
In addition, the motor is driven by a motor other than the motor / generator 5 in order to start by operating the first and second clutches 6 and 7 and the automatic transmission 3 when the main oil pump 9 is not operating. A sub oil pump 26 is provided.

The engine 1, the motor / generator 5, the first clutch 6, and the second clutch 7 that constitute the power train of the hybrid vehicle shown in FIG. 1 are controlled by a system as shown in FIG.
In this embodiment, the first clutch 6 is a normally closed type that is engaged when the hydraulic pressure is not applied and is released when the hydraulic pressure is applied, and the second clutch 7 is engaged when the hydraulic pressure is applied, and is released when the hydraulic pressure is not applied. As a normally open type.

  The control system of FIG. 2 includes an integrated controller 19 having a normal microcomputer for integrated control of the operating point (torque and rotation speed) of the power train, and the operating point of the power train is set to the target engine torque tTe and the target motor. / Generator torque tTm, target transmission torque capacity tTc1 of the first clutch 6, and target transmission torque capacity tTc2 of the second clutch 7.

  The integrated controller 19 includes a signal from the engine speed sensor 10 that detects the engine speed Ne and a motor / generator speed sensor 11 that detects the motor / generator speed Nm in order to determine the operating point of the power train. , A signal from the input rotation sensor 12 that detects the transmission input rotational speed Ni, a signal from the output rotation sensor 13 that detects the transmission output rotational speed No, and an accelerator pedal that represents the required load state of the engine 1 The signal from the accelerator opening sensor 18 that detects the amount of depression (accelerator opening APO) and the state of charge SOC of the battery 27 that stores the electric power for the motor / generator 5 (also referred to as the power that can be taken out, also referred to as the charging rate) Signals from the voltage sensor 16 and the current sensor 17 to be detected are input.

  Among the sensors described above, the engine rotation sensor 10, the motor / generator rotation sensor 11, the input rotation sensor 12, and the output rotation sensor 13 can be arranged as shown in FIG.

  Based on the accelerator opening APO, the battery storage state SOC, and the transmission output rotational speed No (vehicle speed VSP), which is information related to the driving state and the driving state among the input information, the integrated controller 19 Selected driving mode (EV mode, HEV mode) that can realize the driving force of the vehicle, target engine torque tTe, target motor / generator torque tTm, target first clutch transmission torque capacity tTc1, and target second clutch transmission Each of the torque capacities tTc2 is calculated to control the driving force.

The target engine torque tTe calculated by the integrated controller 19 is supplied to the engine controller 20 having an ordinary microcomputer, and the target motor / generator torque tTm calculated by the integrated controller 19 is also a motor having an ordinary microcomputer. / Supplied to the generator controller 21.
The engine controller 20 controls the engine 1 so that the engine torque Te becomes the target engine torque tTe, and the motor / generator controller 21 sets the torque Tm (or the rotational speed Nm) of the motor / generator 5 to the target motor / generator torque tTm. Thus, the motor / generator 5 is controlled via the battery 27 and the inverter 28.
The integrated controller 19 calculates the solenoid current corresponding to the calculated target first clutch transmission torque capacity tTc1 and target second clutch transmission torque capacity tTc2 to the engagement control solenoid valve 14 of the first clutch 6 and the engagement control solenoid valve of the second clutch 7. 15 so that the transmission torque capacity Tc1 of the first clutch 6 matches the target transmission torque capacity tTc1, and the transmission torque capacity Tc2 of the second clutch 7 matches the target second clutch transmission torque capacity tTc2. The first clutch 6 and the second clutch 7 are individually controlled.

  Furthermore, the integrated controller 19 also uses a normal microcomputer to ensure a predetermined line pressure for operating the first and second clutches 6 and 7 and the automatic transmission 3 when the main oil pump 9 is not operating. The sub oil pump controller 22 is controlled, and the sub oil pump controller 22 controls the operation of the motor of the electric sub oil pump 26.

  In the hybrid vehicle having such a configuration, the integrated controller 19 also constitutes the start control device of this embodiment, and therefore, the integrated controller 19 has the first and second clutches when the electric sub-oil pump 26 has failed. In order to ensure a predetermined line pressure for operating 6, 7 and the automatic transmission 3, specifically, in addition to the signal from the accelerator opening sensor 18, the driver's driver for operating the automatic transmission 3 A signal from a shift sensor 23 that detects a shift range of a shift lever (not shown), a signal from a door open / close state sensor 24 that detects an open / close state of the door of the vehicle, and a signal from a direction indicator 25 of the vehicle While inputting at regular time intervals, the control shown in FIGS. 3 and 4 is executed at regular time intervals.

  FIG. 3 is a flowchart showing a program executed by the integrated controller 19 for controlling the motor / generator 5 and the second clutch 7 (CL2) in this embodiment. In this flow, first, in step S1, the electric sub-oil pump Judge whether or not 26 has a failure. In this processing, for example, when the operating current of the electric sub oil pump 26 is too low or excessive, or when the hydraulic pressure in the hydraulic circuit of the automatic transmission 3 does not increase, a failure has occurred in the electric sub oil pump 26. Judge. If it is determined in step S1 that the electric sub oil pump 26 has failed, the process proceeds to the next step S2, and if not, this flow ends. Therefore, this step S1 corresponds to sub oil pump failure determination means.

In step S2, it is determined whether or not there is a start request. In this process, for example, when it is determined that the shift range is the D (drive) range based on the signal from the shift sensor 23 and the vehicle door is closed based on the signal from the door open / close state sensor 24, the accelerator is opened. When it is determined that the accelerator pedal has been depressed by the signal from the degree sensor 18 or the signal from the direction indicator 25 determines that the direction indicator (not shown) has been operated to the start side (the right turn side when the vehicle is on the left side of the vehicle) Judge that there is a request. If it is determined in step S2 that there is a start request, the process proceeds to the next step S3, and if not, this flow ends. Therefore, this step S2 corresponds to a start request determination means.
By doing so, the motor / generator can be stopped and energy consumption can be suppressed except when it is determined that there is an intention to start.

  In step S3, it is determined whether or not the input rotation speed of the automatic transmission (unit) 3, that is, the rotation speed of the main oil pump 9, is equal to or lower than the minimum rotation speed RP1 that can secure the predetermined line pressure of the automatic transmission (unit) 3. If the input rotational speed is less than or equal to RP1, the process proceeds to the next step S4. If the input rotational speed exceeds RP1, this flow is terminated.

  In step S4, the motor / generator 5 is operated (motored) to increase the input rotational speed of the automatic transmission (unit) 3, that is, the rotational speed of the main oil pump 9, and the clutch is operated when a clutch engagement command is issued. Since an oil pressure drop due to the operation may occur, a release command is issued to the second clutch 7 (CL2) to prevent this.

  In the next step S5, whether the input rotation speed of the automatic transmission (unit) 3, that is, the rotation speed of the main oil pump 9, exceeds the minimum rotation speed RP1 that can secure the predetermined line pressure of the automatic transmission (unit) 3 described above. If the input rotation speed exceeds RP1, it is determined that the predetermined line pressure has been secured, and the process proceeds to the next step S6. If the input rotation speed is RP1 or less, the hydraulic pressure is still below the predetermined line pressure. It is determined that the flow is low, and this flow is finished.

  In the next step S6, the vehicle is started by engaging the second clutch 7 (CL2) while controlling the torque capacity, and this flow is finished. In order to prevent the driver from feeling uncomfortable, the torque command value of the second clutch 7 (CL2) is limited to a change rate until the target value is reached as shown in FIG. Therefore, the above steps S3 to S6 correspond to start control means.

  FIG. 4 is a flowchart showing a program executed by the integrated controller 19 for controlling the first clutch 6 (CL1) in this embodiment. In this flow, first, in step S21, as in step S1 of FIG. Then, it is determined whether or not a failure has occurred in the electric sub oil pump 26. If it is determined that a failure has occurred, the process proceeds to the next step S22, and if not, this flow ends.

In step S22, in the same manner as in step S5 of FIG. 3, the minimum rotational speed at which the input rotational speed of the automatic transmission (unit) 3, that is, the rotational speed of the main oil pump 9, can secure the predetermined line pressure of the automatic transmission 3 described above It is determined whether or not the number RP1 has been exceeded.If the input speed exceeds RP1, it is determined that the predetermined line pressure has been secured, and the process proceeds to the next step S23. If the input speed is RP1 or less, the hydraulic pressure is still Is determined to be lower than the predetermined line pressure, the process proceeds to step S25.
Thus, by ensuring that the hydraulic pressure is not applied to the first clutch 6 (CL1) until the predetermined line pressure is ensured, the hydraulic pressure of the second clutch 7 (CL2) can be quickly secured.
The engine 1 is not ignited at the time of step S22, but the first clutch 6 (CL1) is a normally closed type, so the engine 1 is rotated together with the motor / generator 5 while the line pressure is low. When the line pressure rises, it is released and the motor / generator 5 is rotated alone.

In step S23, it is determined whether there is an engine stop request. In this process, a normal idle stop condition (for example, at least one of the cooling water temperature of the engine 1 is not less than the lower limit value of the normal range and the accelerator opening APO is not more than the predetermined value) is satisfied, and the battery charge state SOC is in the charge unnecessary range. When it is equal to or greater than the predetermined lower limit SOC1, it is determined that there is an engine stop request.
By doing this, when the engine stop request condition such as when the battery storage state SOC is sufficiently high is satisfied, the engine 1 is stopped and the rotation of the main oil pump 9 is maintained only by the motor / generator 5. Energy consumption can be suppressed.
Here, the predetermined lower limit SOC1 is set higher than the predetermined lower limit SOC2, which is a normal idle stop condition, by the amount that the motor / generator 5 is driven.
Thus, since the lower limit value of the battery storage state SOC is set higher than the predetermined lower limit value SOC2 that is a normal idle stop condition, it is possible to secure the power for driving the main oil pump 9 with the motor / generator 5. .
If it is determined that there is an engine stop request, the process proceeds to the next step S24, and if not, the process proceeds to step S25. Accordingly, this step S23 corresponds to engine stop request determination means.

  In step S24, the engine stop request is established and the predetermined line pressure is secured, so the first clutch 6 (CL1) is instructed to be released, and this flow is ended. On the other hand, in step S25, since the predetermined line pressure cannot be secured or there is no engine stop request, the first clutch 6 (CL1) is instructed to be engaged, and then the engine 1 is ignited to start idling. finish. As a result, when the predetermined line pressure cannot be secured, and when there is no engine stop request even when the predetermined line pressure can be secured, the first clutch 6 (CL1) is kept in the engaged state.

FIG. 6 is a time chart showing the operating state of the start control device of this embodiment, and the horizontal axis shows time.
At time k1, the sub oil pump controller 22 detects a failure of the sub oil pump 26 and notifies the integrated controller 19 of the failure.
At time k2, the integrated controller 19 detects the driver's accelerator operation and determines that there is an acceleration request. Further, the input rotational speed of the automatic transmission (unit) 3, that is, the rotational speed of the main oil pump 9 = 0 ≦ RP1. Therefore, in order to ensure a predetermined line pressure (hydraulic pressure) of the power train system with the main oil pump 9, the target rotational speed is set to be larger than RP1, and the rotational speed of the motor / generator 5 (MG) is controlled.

At time k3, since the input rotation speed of the automatic transmission (unit) 3 = oil pump rotation speed> RP1, the main oil pump 9 determines that the predetermined line pressure (hydraulic pressure) of the powertrain system has been secured, and the clutch Start the operation of (CL). If the target transmission torque capacity corresponding to the accelerator opening is commanded to the second clutch 7 (CL2) as a torque command value, it suddenly starts and gives the driver a sense of discomfort. Therefore, the integrated controller 19 gradually increases the torque command value for the second clutch 7 (CL2) toward the target transmission torque capacity tTc2 of the second clutch 7 with the time k3 as 0.
By doing so, it is possible to generate a driving force so as not to give the driver a sense of incongruity.
Further, at this time k3, since the battery storage state SOC is higher than the engine start SOC (storage state that requires charging by the engine), it is determined that the engine is to be stopped. Accordingly, the torque command value for the first clutch 6 (CL1) is decreased (hydraulic pressure is applied by the solenoid valve 14 for the first clutch 6), and the first clutch 6 (CL1) is released.
At time k4, the torque command value for the second clutch 7 (CL2) is equal to the target transmission torque capacity tTc2 of the second clutch 7, so the routine shifts to normal control.

  Therefore, according to the start control device of this embodiment, it is possible to generate a sufficient driving force on the drive wheels 2 by controlling the torque capacity of the second clutch 7 using a predetermined line pressure with a sufficiently high height. It is possible to start without causing the driver to feel uncomfortable.

  FIG. 5 is a flowchart showing a program executed by the integrated controller 19 for controlling the first clutch 6 (CL1) in another embodiment of the start control device for a hybrid vehicle of the present invention. The power train of the hybrid vehicle to which this embodiment is applied is the same as the power train shown in FIG. 1, and is controlled by a system similar to the system shown in FIG. In this embodiment, the program executed by the integrated controller 19 for controlling the motor / generator 5 and the second clutch 7 (CL2) is the same as that shown in FIG. However, here, both the first clutch 6 and the second clutch 7 are of a normally open type that is engaged when the hydraulic pressure is applied and is released when the hydraulic pressure is not applied.

  On the other hand, with respect to the control of the first clutch 6 (CL1), in the start control device of this embodiment, in the flow of FIG. 5, first in step S31, as in step S21 of FIG. It is determined whether or not a failure has occurred. If it is determined that a failure has occurred, the process proceeds to the next step S32, and if not, this flow ends.

  In step S32, as in step S22 of FIG. 4, the minimum rotation at which the input rotation speed of the automatic transmission (unit) 3, that is, the rotation speed of the main oil pump 9, can ensure the predetermined line pressure of the automatic transmission 3 described above. If the input speed exceeds RP1, it is determined that the predetermined line pressure has been secured, and the process proceeds to the next step S33. If the input speed is RP1 or less, the hydraulic pressure is still Is determined to be lower than the predetermined line pressure, the process proceeds to step S35.

  In step S33, the presence or absence of an engine stop request is determined in the same manner as in step S23 of FIG. 4. If it is determined that there is no engine stop request, the process proceeds to the next step S34, and if not, the process proceeds to step S35.

  In step S34, the engine stop request is not satisfied and the predetermined line pressure is secured, so the first clutch 6 (CL1) is commanded to be engaged. Next, the engine 1 is ignited to start idling, and this flow is ended. On the other hand, in step S35, since the predetermined line pressure cannot be secured or there is an engine stop request, the first clutch 6 (CL1) is instructed to be released and this flow is ended. As a result, when the predetermined line pressure cannot be secured, and when there is no engine stop request even if the predetermined line pressure can be secured, the first clutch 6 (CL1) is kept in the released state.

FIG. 7 is a time chart showing the operating state of the start control device of this embodiment, and the horizontal axis shows time.
At time k11, the sub oil pump controller 22 detects a failure of the sub oil pump 26 and notifies the integrated controller 19 of the failure.
At time k12, the integrated controller 19 detects the driver's accelerator operation and determines that there is an acceleration request. Further, the input rotational speed of the automatic transmission (unit) 3, that is, the rotational speed of the main oil pump 9 = 0 ≦ RP1. Therefore, in order to ensure a predetermined line pressure (hydraulic pressure) of the power train system with the main oil pump 9, the target rotational speed is set to be larger than RP1, and the rotational speed of the motor / generator 5 (MG) is controlled.

At time k13, since the input rotation speed of the automatic transmission (unit) 3 = oil pump rotation speed> RP1, the main oil pump 9 determines that the predetermined line pressure (hydraulic pressure) of the powertrain system has been secured, and the clutch Start the operation of (CL). If the target transmission torque capacity corresponding to the accelerator opening is commanded to the second clutch 7 (CL2) as a torque command value, it suddenly starts and gives the driver a sense of discomfort. Therefore, the integrated controller 19 gradually increases the torque command value for the second clutch 7 (CL2) toward the target transmission torque capacity tTc2 of the second clutch 7 with the time k13 as 0.
By doing so, it is possible to generate a driving force so as not to give the driver a sense of incongruity.
Further, at this time k13, since the battery storage state SOC is lower than the engine start SOC (storage state that requires charging by the engine), it is determined to start the engine. Accordingly, the torque command value for the first clutch 6 (CL1) is increased (hydraulic pressure is applied by the solenoid valve 14 for the first clutch 6), and the first clutch 6 (CL1) is engaged.

At time k14, the engine speed is equal to the input speed of the automatic transmission (unit) 3, and the clutch 6 (CL1) is completely engaged. Since the sub oil pump is out of order, the battery / power storage state SOC is charged by the motor / generator 5 (MG) so as to become the predetermined lower limit SOC1 that is set higher than the predetermined lower limit SOC2 that is the idle stop condition in the normal state. .
Thus, since the lower limit value of the battery storage state SOC is set higher than the predetermined lower limit value SOC2 that is a normal idle stop condition, it is possible to secure the power for driving the main oil pump 9 with the motor / generator 5. .
At time k15, the torque command value for the second clutch 7 (CL2) is equal to the target transmission torque capacity tTc2 of the second clutch 7, so the routine shifts to normal control.

  Therefore, according to the start control device of this embodiment, it is possible to generate a sufficient driving force on the drive wheels 2 by controlling the torque capacity of the second clutch 7 using a predetermined line pressure with a sufficiently high height. It is possible to start without causing the driver to feel uncomfortable.

Although the present invention has been described based on the illustrated examples, the present invention is not limited to the above-described examples, and various modifications can be made within the scope of the claims. For example, the main oil pump is provided on the transmission side. Instead, it may be provided on the motor / generator side, and the transmission-side friction element may be detachably coupled between the motor / generator and the transmission input shaft.
In the above example, the main oil pump is driven only by the motor / generator until it exceeds the predetermined rotational speed. For example, when the engine side friction element is a normally closed type, the main oil pump is replaced by the motor / generator and the engine instead. Alternatively, it may be driven only by the engine.

  Thus, according to the start control device of the present invention, a sufficient driving force can be generated in the driving wheel by controlling the torque capacity of the friction element on the transmission side using a sufficiently high predetermined line pressure. It is possible to start without causing a sense of incongruity.

In the start control device of the present invention, the start control means may be configured such that when the sub oil pump failure determination means determines that there is a failure in the electric sub oil pump, the motor does not cause a failure. It is also possible to maintain a high management value for the battery that exchanges power with the generator.
In this way, it is possible to secure the power for driving the main oil pump with the motor / generator.

Further, in the start control device of the present invention, the start request determination means is configured to determine whether the start request is present based on at least one of the shift range of the transmission, the door open / close state, the accelerator opening, and the direction indicator. It is good also as what judges.
In this way, unless the accelerator is on, the shift range is drive (DR), the door is closed, or the direction indicator is flashing on the start side, or when it is determined that there is an intention to start Can stop energy consumption by stopping the motor / generator.

Furthermore, the start control device of the present invention comprises an engine stop request determining means for determining whether or not there is an engine stop request,
The engine-side friction element is opened by hydraulic pressure and is in a fastening state without hydraulic pressure,
The start control means commands the fastening of the engine side friction element before securing the predetermined line pressure, and after the predetermined line pressure is secured, the presence or absence of the engine stop request determined by the engine stop request determining means In response to this, the engine-side friction element may be instructed to be released or engaged.
In this way, since the hydraulic pressure is not applied to the engine-side friction element until the predetermined line pressure is ensured, it is possible to quickly ensure the hydraulic pressure of the transmission-side friction element.

On the other hand, the start control device of the present invention comprises an engine stop request determining means for determining the presence or absence of an engine stop request,
The engine side friction element is fastened by hydraulic pressure and is opened without hydraulic pressure,
The start control means gives an instruction to release the engine side friction element before securing the predetermined line pressure, and after securing the predetermined line pressure, the presence or absence of the engine stop request determined by the engine stop request determining means The engine-side friction element may be instructed or released according to the above.
In this way, since the hydraulic pressure is not applied to the engine-side friction element until the predetermined line pressure is ensured, it is possible to quickly ensure the hydraulic pressure of the transmission-side friction element.

Further, in the start control device of the present invention, the engine stop request determining means determines whether or not the engine stop request is present based on at least one of the engine coolant temperature and the accelerator opening in addition to the battery management value. It is also good.
In this way, when the engine stop request condition is satisfied, such as when the battery management value is sufficiently high, the engine is stopped and the rotation of the main oil pump is maintained only by the motor / generator. Can be suppressed.

Further, in the start control device of the present invention, the torque capacity control of the transmission side friction element by the start control means is performed until the torque command value to the transmission side friction element is secured until the predetermined line pressure is ensured. It is good also as what is gradually raised to the value corresponded to an accelerator opening after ensuring the said predetermined line pressure.
In this way, it is possible to generate a driving force so as not to give the driver a sense of incongruity.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view showing a power train of a front engine / rear wheel drive hybrid vehicle to which an embodiment of a start control device of the present invention is applied. It is a block diagram which shows the control system of the power train shown in FIG. It is a flowchart which shows the program which an integrated controller performs for control of a motor / generator and a 2nd clutch in the said Example. It is a flowchart which shows the program which an integrated controller performs in order to control a 1st clutch in the said Example. 6 is a flowchart showing a program executed by the integrated controller for controlling the first clutch in another embodiment of the start control device of the present invention. It is a time chart which shows the operating state of the start control apparatus of a previous Example. It is a time chart which shows the operating state of the starting control apparatus of a later Example.

Explanation of symbols

1 engine
1a Output shaft
2 Drive wheel (rear wheel)
3 Automatic transmission
3a Input shaft
3b Output shaft
4 Transmission shaft
5 Motor / generator
6 First clutch
7 Second clutch
8 Differential gear unit
9 Main oil pump
10 Engine rotation sensor
11 Motor / generator rotation sensor
12 Transmission input rotation sensor
13 Transmission output rotation sensor
14 Solenoid valve for first clutch
15 Solenoid valve for second clutch
16 Voltage sensor
17 Current sensor
18 Accelerator position sensor
19 Integrated controller
20 Engine controller
21 Motor / generator controller
22 Sub oil pump controller
23 Shift sensor
24 Door open / closed state sensor
25 Direction indicator
26 Electric sub oil pump
27 battery
28 Inverter

Claims (7)

An engine, a transmission having an input shaft drivingly coupled to the output shaft of the engine and an output shaft drivingly coupled to a drive wheel, and a motor / generator interposed between the engine output shaft and the transmission input shaft; An engine-side friction element that detachably connects the engine output shaft and the motor / generator, and between the motor / generator and the transmission input shaft or between the transmission input shaft and the transmission output shaft by hydraulic pressure. A transmission-side friction element that is detachably coupled, and is inserted between the motor / generator and the transmission-side friction element and driven by at least one of the engine and the motor / generator to at least the transmission-side friction element. A drive system having a main oil pump for supplying hydraulic pressure;
An electric sub-oil pump that is driven by a motor other than the motor / generator and supplies hydraulic pressure to at least the transmission-side friction element;
In a hybrid vehicle comprising
A start request determining means for determining presence or absence of a start request;
Sub oil pump failure determination means for determining whether or not the electric sub oil pump has failed;
When the sub oil pump failure determination means determines that there is a failure in the electric sub oil pump and the rotation number of the main oil pump is equal to or less than a predetermined value, the start request determination means determines that there is a start request, With the transmission-side friction element being instructed to be released, at least one of the engine and the motor / generator increases the rotational speed of the main oil pump until it exceeds the predetermined value so as to ensure a predetermined line pressure. Start control means for generating a driving force on the driving wheel by controlling the torque capacity of the transmission-side friction element after securing the line pressure;
A start control device for a hybrid vehicle, comprising:   When the sub oil pump failure determination unit determines that the electric sub oil pump has a failure, the start control unit manages the battery that exchanges power with the motor / generator than when the sub oil pump failure determination unit determines that there is no failure. The start control device for a hybrid vehicle according to claim 1, wherein the value is kept high.   The start request determination means determines presence or absence of the start request based on at least one of a shift range of the transmission, a door open / close state, an accelerator opening, and a direction indicator. 3. A start control device for a hybrid vehicle according to 1 or 2. Engine stop request determination means for determining whether or not there is an engine stop request,
The engine-side friction element is opened by hydraulic pressure and is in a fastening state without hydraulic pressure,
The start control means commands the fastening of the engine side friction element before securing the predetermined line pressure, and after the predetermined line pressure is secured, the presence or absence of the engine stop request determined by the engine stop request determining means The start control device for a hybrid vehicle according to any one of claims 1 to 3, wherein the engine-side friction element is commanded to be released or engaged according to Engine stop request determination means for determining whether or not there is an engine stop request,
The engine side friction element is fastened by hydraulic pressure and is opened without hydraulic pressure,
The start control means gives an instruction to release the engine side friction element before securing the predetermined line pressure, and after securing the predetermined line pressure, the presence or absence of the engine stop request determined by the engine stop request determining means The start control device for a hybrid vehicle according to any one of claims 1 to 3, wherein the engine-side friction element is commanded to be engaged or disengaged in response to the command.   6. The engine stop request determining means determines whether or not there is an engine stop request based on at least one of an engine coolant temperature and an accelerator opening in addition to a management value of the battery. Hybrid vehicle start control device.   In the torque capacity control of the transmission side friction element by the start control means, the torque command value to the transmission side friction element is maintained at 0 until the predetermined line pressure is ensured, and after the predetermined line pressure is ensured. The start control device for a hybrid vehicle according to any one of claims 1 to 6, wherein the start-up control device gradually increases to a value corresponding to the accelerator opening.

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