JP2010210074A - Control device of drive device for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance drivability by determining an appropriate gear stage during a power-on downshift. <P>SOLUTION: During the determination of the power-on downshift of an automatic transmission 10 in pressing down an accelerator pedal, the gear stage GS at which the maximum driving force Fmax which can be generated after the power-on downshift exceeds the prediction of a requested driving force Freqp is determined as a targeted gear stage GS<SP>*</SP>. Consequently, the occurrence of the power-on downshift in additionally pressing down an accelerator pedal 52 is inhibited, that is, a so-called busy shift is inhibited. In addition, a predicted demand driving force Freqp is corrected to be reduced as an estimated amount of change ΔN<SB>E</SB>in an engine rotation speed before and after the power-on downshift increases. Therefore, the maximum driving force Fmax after the power-on downshift which exceeds the predicted demand driving force Freqp is allowed to be relatively small, and the gear stage GS on a higher vehicle speed side is determined as a target gear stage GS<SP>*</SP>, whereby the feeling of excessive step-down of the gear stage is mitigated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control device for a vehicle drive device that controls a shift of a stepped automatic transmission based on a required amount of a vehicle by a driver, and particularly relates to a downshift at power-on.

  For example, a target driving force (required driving force) is calculated based on a driver's requested amount (driver requested amount) such as an accelerator operation amount, and a shift of the stepped automatic transmission is performed so that the required driving force is obtained. A control device for a vehicular drive device that performs the above is well known. For example, the control apparatus of the automatic transmission shown by patent documents 1-4 is it. In such a vehicle, for example, a shift is determined based on a vehicle state represented by an accelerator operation amount (or required driving force, etc.) and a vehicle speed from a known shift line, and the determined gear stage (shift stage) is determined. The shift of the automatic transmission is executed so as to be obtained. Such shift lines include, for example, “execution of a shift from an actual gear stage currently being traveled” and “a target gear stage that is a shift destination is a gear stage based on the shift line”. It is considered to have information. For this reason, there is a possibility that the target gear stage based on the shift line cannot obtain a sufficient driving force with respect to the expectation even though the driver depresses the accelerator pedal in anticipation of an increase in driving force due to the downshift. In other words, the target gear stage based on the shift line is statically determined as the gear stage of the shift destination, for example, simply because the amount of depression of the accelerator pedal exceeds a threshold value (shift point). Therefore, there is a possibility that an appropriate gear is not selected according to the driver's operation. As a result, the accelerator pedal is further depressed, and a power-on downshift is continuously generated, so that a change in the engine rotation speed is continuously generated, which may be a so-called busy shift. As a result, the driver may feel busy or the acceleration may be lost due to continuous shifting, which may reduce drivability.

  On the other hand, as a countermeasure against the above-described busy shift, in Patent Document 5, for each gear stage, an evaluation function is created based on the marginal driving force up to the maximum driving force and the marginal rotational speed up to the maximum rotational speed of the engine. It is disclosed that the gear stage having the maximum evaluation function is set as the target gear stage. As described above, the technique described in Patent Document 5 secures flexibility for driver operation by dynamically calculating the two pieces of information described above.

JP 2007-182765 A JP 2007-64180 A JP 2005-188544 A JP 2000-329226 A JP-A-4-95655

  However, in the above-mentioned Patent Document 5, the above-described two pieces of information are determined by the margin driving force and the margin rotation speed, but a shift pattern based on other information such as fuel consumption cannot be determined. For this reason, in addition to the above two pieces of information, for example, dynamically calculating all the information of a so-called shift line such as fuel efficiency improvement may be complicated and give a large load to the calculation. Separately from this, in the power-on downshift, the driving force is increased by lowering (dropping) the gear stage to the low vehicle speed side, and at this time, the engine rotational speed also increases at the same time. Therefore, depending on how the engine speed is increased, that is, depending on the selected gear stage, the driver is not able to secure the intended driving force by the power-on downshift. There is a possibility that drivability may be reduced due to a strong feeling. The above-described problems are not known, and it has not been proposed to improve the drivability by suppressing the busy feeling or the feeling of dropping too much without giving a great load to the gear position determination.

  The present invention has been made against the background of the above circumstances, and the object of the present invention is to determine an appropriate gear stage at the time of a power-on downshift accompanying an increase in the required amount of the vehicle by the driver. Another object of the present invention is to provide a control device for a vehicle drive device that can improve drivability.

  To achieve the above object, the gist of the present invention is that (a) a shift of a stepped automatic transmission is performed so that a required driving force-related value calculated based on a required amount of a vehicle by a driver is obtained. (B) When a power-on downshift of the stepped automatic transmission accompanying an increase in the required amount is determined, it can occur after the power-on downshift In other words, the gear position at which the maximum driving force-related value exceeds a predetermined threshold value based on the required amount is determined as the target gear position of the downshift destination.

  In this way, when a power-on downshift associated with an increase in the required amount of the vehicle by the driver is determined, the maximum driving force-related value that can be generated after the power-on downshift is determined in advance based on the required amount by the driver. Since the gear stage that exceeds the set threshold is determined as the target gear stage of the downshift destination, the power-on downshift to an appropriate gear stage that satisfies the driving force-related value that the driver intends (expects) Is executed. Therefore, the occurrence of a power-on downshift accompanying further depression of the accelerator pedal is suppressed, and so-called busy shift is suppressed. Therefore, an appropriate gear stage is determined at the time of a power-on downshift accompanying an increase in the required amount by the driver, and the drivability can be suppressed and the drivability can be improved.

  Here, preferably, the estimated rotational speed change amount of the driving force source before and after the power-on downshift is calculated, and the estimated rotational speed change is reduced so that the threshold value is decreased as the estimated rotational speed change amount is larger. The threshold is corrected based on the amount. In this way, as the estimated rotational speed change amount is larger, the maximum driving force-related value after the power-on downshift that exceeds the threshold value is relatively small, and the gear stage on the higher vehicle speed side is reduced. It is determined as the target gear stage to shift to. In other words, the greater the estimated rotational speed change amount, the more the gear stage is suppressed from being lowered to the low vehicle speed side. Therefore, when a power-on downshift accompanying an increase in the required amount by the driver is performed, an appropriate gear stage is determined, and the drivability can be improved by suppressing an excessive feeling of the gear stage.

  Preferably, the threshold value is corrected when the estimated rotational speed change amount exceeds a predetermined change amount. In this way, only when the estimated rotational speed change amount is large enough to exceed the predetermined change amount, that is, only when the user feels that the gear stage is too weak, the gear stage is suppressed from being lowered too much to the low vehicle speed side. . On the other hand, when the estimated amount of change in the rotational speed is small enough to be within the range of the predetermined amount of change, that is, when the user feels that the gear stage is not excessively lowered, the driver's intended (expected) driving force related value should be satisfied. A power-on downshift to the appropriate gear stage is performed.

  Preferably, the threshold value is calculated based on the required driving force-related value, a differential value of the required driving force-related value, and a second-order differential value of the required driving force-related value. And the highest gear among the gears where the maximum driving force-related value exceeds the predicted required driving force-related value is determined as the target gear. In this way, an appropriate gear stage is determined without applying a great load during a power-on downshift associated with an increase in the amount requested by the driver.

  Preferably, when the power-on downshift is determined, a gear position on the lower vehicle speed side with respect to the actual gear position currently being traveled is set as a temporary target gear position, and the predicted request drive is performed. While the force-related value exceeds the maximum driving force-related value that can be generated in the temporary target gear stage, the temporary target gear stage is sequentially set to a gear stage on the lower vehicle speed side while the temporary target gear stage is set. Is determined as the target gear stage when the maximum driving force-related value that can be generated in step S is equal to or greater than the predicted required driving force-related value. In this way, a more appropriate gear stage can be determined without applying a great load during a power-on downshift accompanying an increase in the amount requested by the driver.

  Preferably, the estimated rotational speed change amount is converted into a rotation equivalent driving force related value by a predetermined constant, and the predicted required driving force related value is subtracted by the rotation equivalent driving force related value. to correct. In this way, when the power-on downshift is accompanied by an increase in the amount requested by the driver, the feeling of excessive gear reduction is more appropriately suppressed.

  Preferably, in the stepped automatic transmission, a plurality of gear stages (shift stages) are selected by selectively connecting rotating elements of a plurality of planetary gear units by the wet friction engagement device. For example, it can be achieved by various planetary gear type multi-stage transmissions such as four forward stages, five forward stages, six forward stages, and more gear stages. As wet friction engagement devices in this planetary gear type multi-stage transmission, hydraulic friction engagement devices such as multi-plate and single-plate clutches and brakes that are engaged by a hydraulic actuator are widely used. An oil pump that supplies hydraulic oil for engaging the hydraulic friction engagement device may be driven by a driving force source for traveling and discharges hydraulic oil, for example, but is arranged separately from the driving force source. It may be driven by a dedicated electric motor provided.

  Preferably, the hydraulic control circuit including the hydraulic friction engagement device is responsive to, for example, supplying output hydraulic pressure of a linear solenoid valve directly to a hydraulic actuator (hydraulic cylinder) of the hydraulic friction engagement device. However, it is also possible to control the shift control valve by using the output hydraulic pressure of the linear solenoid valve as a pilot hydraulic pressure, and to supply hydraulic oil from the control valve to the hydraulic actuator.

  Preferably, one linear solenoid valve is provided, for example, corresponding to each of a plurality of hydraulic friction engagement devices. However, the linear solenoid valves are not engaged at the same time or controlled to be engaged or released. When there are a plurality of hydraulic friction engagement devices, various modes are possible, such as providing a common linear solenoid valve for them. In addition, it is not always necessary to control the hydraulic pressure of all the hydraulic friction engagement devices with the linear solenoid valve, and pressure control means other than the linear solenoid valve, such as duty control of the ON-OFF solenoid valve for part or all of the hydraulic control. You can go there.

  Preferably, an engine that is an internal combustion engine such as a gasoline engine or a diesel engine is widely used as the driving force source. Further, an electric motor or the like may be used in addition to this engine as an auxiliary driving power source. Alternatively, only an electric motor may be used as a driving force source for traveling.

  In this specification, “supplying hydraulic pressure” means “applying hydraulic pressure” or “supplying hydraulic oil controlled to the hydraulic pressure”.

1 is a skeleton diagram illustrating a configuration of a vehicle drive device to which the present invention is applied. FIG. 2 is an operation chart for explaining combinations of operations of friction engagement devices when a plurality of gear stages of the stepped automatic transmission of FIG. 1 are established. It is a block diagram explaining the principal part of the control system with which the vehicle drive device of FIG. 1 is provided. FIG. 4 is a circuit diagram relating to a linear solenoid valve that controls the operation of each hydraulic actuator of clutches C1 and C2 and brakes B1 to B3 in the hydraulic control circuit of FIG. 3. It is a functional block diagram explaining the principal part of the control function of the electronic control apparatus of FIG. It is a figure which shows an example of the relationship (driving force map) calculated | required experimentally beforehand and memorize | stored with the accelerator opening as a parameter. It is a figure which shows an example of the shift map used for determination of the gear stage of the stepped automatic transmission of FIG. It is a figure which shows an example of the relationship (engine torque map) calculated | required experimentally beforehand and memorize | stored by using the throttle valve opening as a parameter as an engine rotational speed and an engine torque estimated value. It is a conceptual diagram at the time of calculating a prediction required driving force. The main part of the control operation of the electronic control device of FIG. 3, that is, the control operation for improving the drivability by determining an appropriate gear stage at the time of the power-on downshift accompanying the increase in the required amount of the vehicle by the driver is explained. It is a flowchart to do.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a skeleton diagram illustrating the configuration of a vehicle drive device 8 to which the present invention is applied. FIG. 2 shows a frictional engagement element, that is, a frictional engagement when a plurality of gear stages GS (shift stage GS) of a stepped automatic transmission (hereinafter referred to as an automatic transmission) 10 provided in the vehicle drive device 8 is established. It is an operation | movement table | surface explaining the operation state of a combination apparatus. The vehicle drive device 8 includes an engine 30, which is a driving power source, a torque converter 32, an automatic transmission 10, a differential gear device 40, a pair of axles 44, and the like (see FIG. 3). The automatic transmission 10 is preferably used for an FF vehicle mounted in the left-right direction (horizontal) of the vehicle, and is a single pinion type first in a transmission case 26 as a non-rotating member attached to the vehicle body. A first transmission 14 configured mainly with the planetary gear unit 12, a second pinion type second planetary gear unit 16, and a single pinion type third planetary gear unit 18 mainly configured with a Ravigneaux type. The second transmission unit 20 is provided on a common axis C, and the rotation of the input shaft 22 is shifted and output from the output rotation member 24. The input shaft 22 corresponds to an input member, and is a turbine shaft of a torque converter 32 as a fluid transmission device that is rotationally driven by the engine 30. The output rotating member 24 corresponds to the output member of the automatic transmission 10, and an output gear that meshes with the differential driven gear (large-diameter gear) 42 to transmit power to the differential gear device 40 shown in FIG. That is, it functions as a differential drive gear. The output of the engine 30 is transmitted to the pair of drive wheels 46 via the torque converter 32, the automatic transmission 10, the differential gear device 40, and the pair of axles 44. The automatic transmission 10 and the torque converter 32 are substantially symmetrical with respect to the center line (axial center) C, and the lower half of the center line C is omitted in the skeleton diagram of FIG.

  The torque converter 32 includes a lockup clutch 34 as a lockup mechanism that directly transmits the power of the engine 30 to the input shaft 22 without passing through fluid. The lock-up clutch 34 is a hydraulic friction clutch that is frictionally engaged by a differential pressure ΔP between the hydraulic pressure in the engagement-side oil chamber 36 and the hydraulic pressure in the release-side oil chamber 38, and is completely engaged (locked). The power of the engine 30 is directly transmitted to the input shaft 22 by being turned on. Further, the differential pressure ΔP, that is, the torque capacity is feedback-controlled so as to be engaged in a predetermined slip state, so that the turbine shaft (input shaft 22) has a predetermined slip amount of, for example, about 50 rpm when the vehicle is driven (power on). Is rotated following the output shaft of the engine 30, while the output shaft of the engine 30 is rotated following the turbine shaft with a predetermined slip amount of, for example, about -50 rpm when the vehicle is not driven (power off).

  The automatic transmission 10 corresponds to the combination of any one of the rotational elements (sun gears S1 to S3, carriers CA1 to CA3, ring gears R1 to R3) of the first transmission unit 14 and the second transmission unit 20. Six forward gear stages (forward shift stages) from the first gear stage “1st” to the sixth gear stage “6th” are established, and the reverse gear stage (reverse shift stage) of the reverse gear stage “R” is established. It is done. As shown in FIG. 2, for example, in the forward gear stage, the first speed gear stage is engaged by the engagement of the clutch C1 and the brake B2, and the second speed gear stage is engaged by the engagement of the clutch C1 and the brake B1, and the clutch C1 is engaged. The third gear is set by engagement with the brake B3, the fourth gear is set by engagement of the clutch C1 and the clutch C2, and the fifth gear is set by engagement of the clutch C2 and the brake B3. The sixth gear is established by engaging the brake B1. Further, the reverse gear stage is established by the engagement of the brake B2 and the brake B3, and the neutral state is established by releasing any of the clutches C1, C2 and the brakes B1 to B3.

The operation table of FIG. 2 summarizes the relationship between the above-mentioned gear stages GS and the operation states of the clutches C1, C2 and the brakes B1 to B3, where “◯” indicates engagement and “◎” indicates engine braking only. Represents engagement. Since the brake B2 that establishes the first gear stage “1st” is provided with the one-way clutch F1 in parallel, it is not always necessary to engage the brake B2 when starting (acceleration). The gear ratio γGS of each gear stage GS (= the rotational speed N _IN of the input shaft 22 / the rotational speed N _OUT of the output rotating member 24) is the first planetary gear device 12, the second planetary gear device 16, and the third planetary gear device 16. Each gear ratio of the planetary gear unit 18 (= the number of teeth of the sun gear / the number of teeth of the ring gear) ρ1, ρ2, and ρ3 is appropriately determined.

  The clutches C1 and C2 and the brakes B1 to B3 (hereinafter simply referred to as the clutch C and the brake B unless otherwise distinguished) are hydraulic friction engagement elements that are controlled by a hydraulic actuator such as a multi-plate clutch or a brake. (Hydraulic friction engagement device), the engagement and release states are switched by the excitation, de-excitation and current control of the linear solenoid valves SL1 to SL5 of the hydraulic control circuit 50 (see FIG. 3) and the engagement and release The transient oil pressure at the time is controlled.

  FIG. 3 is a block diagram illustrating a main part of an electrical control system provided in the vehicle for controlling the automatic transmission 10 of FIG. The electronic control device 100 includes, for example, a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like, and the CPU uses a temporary storage function of the RAM according to a program stored in the ROM in advance. By performing signal processing, output control of the engine 30, shift control of the automatic transmission 10, on / off control of the lockup clutch 34, and the like are executed, and for engine control and linear solenoid valve SL 1 as necessary. Are configured separately for shift control for controlling SL5 and for lockup clutch control for controlling the linear solenoid valve SLU and the solenoid valve SL.

In FIG. 3, an accelerator operation amount sensor 54 for detecting a so-called accelerator opening degree Acc, which is an operation amount of the accelerator pedal 52 as a required amount (driver required amount) for the vehicle by the driver, and an output shaft rotation speed of the power source intake air of the rotational engine speed sensor 56 for detecting the speed N _E, the cooling water temperature sensor 58 for detecting the cooling water temperature T _W of the engine 30, for detecting an intake air quantity Q of the engine 30 of the engine 30 rotation amount sensor 60, the intake air temperature sensor 62 for detecting the temperature T _a of intake air, a throttle valve opening sensor 64 for detecting an opening theta _TH of the electronic throttle valve, the vehicle speed V (output rotating member 24 a vehicle speed sensor 66 for detecting the corresponding) to the speed N _OUT, to detect the presence or absence of the operation of the foot brake pedal 68 is a service brake Turbine speed for detecting the rotational speed N _IN of the brake switch 70, a lever position sensor 74 for detecting a lever position (operating position) P _SH of the shift lever 72, turbine rotational speed N _T i.e. the input shaft 22 for sensor 76, such as aT oil temperature sensor 78 for detecting an aT oil temperature T _oIL is a temperature of the hydraulic oil in the hydraulic control circuit 50 is provided with, etc. these sensors and switches, the engine rotational speed N _E , Engine cooling water temperature T _W , intake air amount Q, intake air temperature T _A , throttle valve opening θ _TH , vehicle speed V, output shaft rotational speed N _OUT , presence / absence of brake operation, lever position P _SH of shift lever 72, turbine A signal indicating the rotational speed N _T (= input shaft rotational speed N _IN ), AT oil temperature T _OIL, etc. is an electronic control unit. 100 is supplied.

4 is a linear solenoid valve that controls the operation of the hydraulic actuators (hydraulic cylinders) A _C1 , A _C2 , A _B1 , A _B2 , A _B3 of the clutches C1, C2 and brakes B1 to B3 in the hydraulic control circuit 50. It is a circuit diagram regarding SL1 to SL5. In FIG. 4, the hydraulic pressures A _C1 , A _C2 , A _B1 , A _B2 , A _B3 are applied to the line hydraulic pressure PL by linear solenoid valves SL1 to SL5, respectively, according to command signals from the electronic control unit 100. The pressure is adjusted to P _C1 , P _C2 , P _B1 , P _B2 , and P _B3 and supplied directly. The line oil pressure PL is generated from, for example, a mechanical oil pump 28 (see FIG. 1) rotated by the engine 30 by a relief type pressure regulating valve (regulator valve) (not shown) or an electric oil pump (not shown). Is adjusted to a value corresponding to the engine load or the like represented by the accelerator opening or the throttle opening.

The linear solenoid valves SL1 to SL5 have basically the same configuration, and are excited and de-energized independently by the electronic control unit 100, and the hydraulic pressure of each hydraulic actuator A _C1 , A _C2 , A _B1 , A _B2 , A _B3 . Are independently regulated to control the engagement pressures P _C1 , P _C2 , P _B1 , P _B2 , and P _{B3 of} the clutches C1 to C4 and the brakes B1 and B2. Then, in the automatic transmission 10, for example, as shown in the engagement operation table of FIG. 2, each gear stage GS is established by engaging a predetermined engagement device. In the shift control of the automatic transmission 10, for example, a so-called clutch-to-clutch shift is performed in which release and engagement of the clutch C and the brake B involved in the shift are controlled simultaneously. For example, as shown in the engagement operation table of FIG. 2, in the upshift from the third speed to the fourth speed, the brake B3 is released and the clutch C2 is engaged, and the release transient hydraulic pressure of the clutch C2 is suppressed so as to suppress the shift shock. And the engagement transient hydraulic pressure of the clutch C4 are appropriately controlled.

  Returning to FIG. 3, the solenoid valve SL and the linear solenoid valve SLU provided in the hydraulic control circuit 50 are excited and de-energized by the electronic control unit 100, and the lockup clutch 34 is turned on (engaged) and turned off by the solenoid valve SL. (Release) is switched to the ON side, and the torque capacity of the lockup clutch 34, that is, the differential pressure ΔP, is regulated by the linear solenoid valve SLU, so that the torque converter 32 is slipped or locked up. (Complete engagement) is controlled.

FIG. 5 is a functional block diagram illustrating the main part of the control function of the electronic control device 100. In FIG. 5, the setting unit, that is, the setting unit 110 sets the target engine torque T _E ^* and the target gear stage GS ^* based on the vehicle state represented by the accelerator opening Acc and the vehicle speed V. For example, the setting unit 110 includes a required driving force calculation unit that calculates the required driving force Freq, that is, a required driving force calculation unit 112, a target gear stage determination unit that determines the target gear stage GS ^*, that is, a target gear stage determination unit 114, A target engine torque calculation unit for calculating the target engine torque T _E ^*, that is, target engine torque calculation means 116 is provided.

  The required driving force calculation means 112 is actually calculated from a relationship (driving force map) obtained and stored experimentally in advance between the vehicle speed V and the required driving force Freq with the accelerator opening Acc as shown in FIG. 6 as a parameter. Based on the accelerator opening Acc and the vehicle speed V, a required driving force Freq (= map (accelerator opening Acc, vehicle speed V)) is obtained. The driving force map of FIG. 6 is set so that the required driving force Freq increases as the vehicle speed V decreases and the accelerator operation amount Acc increases.

The target gear stage determining means 114 determines an optimum target gear stage GS ^* in consideration of fuel consumption and drivability in order to obtain the required driving force Freq calculated by the required driving force calculating means 112. For example, the target gear stage determining means 114 determines the actual accelerator opening from the relationship (shift diagram, shift map) as shown in FIG. 7 stored in advance in consideration of fuel consumption and drivability in order to obtain the required driving force Freq. The target gear stage GS ^* is determined based on the degree Acc (or the required driving force Freq) and the vehicle speed V. In the shift diagram of FIG. 7, a solid line is a shift line (upshift line) for determining an upshift, and a broken line is a shift line (downshift line) for determining a downshift. Further, the shift line in the shift diagram of FIG. 7 indicates whether the actual vehicle speed V crosses the line on the horizontal line indicating the actual accelerator opening Acc (or the required driving force Freq), that is, the shift on the shift line. to execute value is for determining whether exceeds (shift point threshold) V _S, also will have been previously stored as a series of the values V _S that shift point threshold. From another point of view, the shift line in the shift diagram of FIG. 7 is, for example, whether or not the actual accelerator opening Acc (or required driving force Freq) exceeds the line on the vertical line indicating the actual vehicle speed V, i.e., the shift. This is for determining whether or not the value (shift point threshold) Acc _S (F ^* _S ) to be subjected to the shift on the line has been exceeded, and this value Acc _S (F ^* _S ), that is, a series of shift point thresholds. It is also stored in advance.

The target engine torque calculating means 116 is, for example, a required driving force Freq calculated by the required driving force calculating means 112 and a target gear speed determined by the target gear speed determining means 114 from the relationship of the following equation (1) stored in advance. A target engine torque T _E ^* is calculated based on GS ^* . Here, r _D is the effective tire radius of the drive wheel 46, γGS ^* is the gear ratio of the automatic transmission 10 when the target gear stage GS ^* is achieved, and i is the output rotating member 24 (diff drive gear) and the differential driven gear 42. The final speed reduction ratio of the final speed reducer or the like constituted by and t is the torque ratio of the torque converter 32.
T _E ^* = (F ^* × r _D ) / (γGS ^* × i × t) (1)

The engine torque control unit, that is, the engine torque control means 118 controls the output of the engine 30 so that the target engine torque T _E ^* calculated by the target engine torque calculation means 116 is obtained. For example, the engine torque control means 118 is previously experimentally sought stored relationship between the engine rotational speed N _E and the engine torque estimated value T _E0 throttle valve opening theta _TH as shown in FIG. 8 as a parameter ( the target engine torque T _E ^* to calculate a target throttle opening theta _TH ^* to be the engine torque estimated value T _E0 for obtained based on the actual engine rotational speed N _E from the engine torque map). The engine torque control means 118 controls the opening / closing of the electronic throttle valve so as to achieve the target throttle opening θ _TH ^* via an engine output control device (not shown) such as a throttle actuator, a fuel injection device, and an ignition device. Then, the fuel injection amount and injection timing by the fuel injection device are controlled, and the output control of the engine 30 is executed so as to obtain the target engine torque T _E ^* by controlling the ignition timing by the ignition device.

The shift control unit, that is, the shift control means 120 is engaged with the clutches C1 and C2 and the brakes B1 to B3 via the hydraulic control circuit 50 so that the target gear stage GS ^* determined by the target gear stage determination unit 114 is obtained. By controlling the release, shift control is performed so that the actual gear stage GS of the automatic transmission 10 matches the target gear stage GS ^* .

Here, in the shift line as shown in FIG. 7, for example, which is the basis for determining the target gear stage GS ^* by the target gear stage determining means 114, in addition to determining whether or not to execute the shift itself, The gear stage is also determined at the same time. That is, the target gear stage GS ^* based on the shift line is statically determined as the gear stage of the shift destination simply because the vehicle state exceeds the shift point threshold. For example, the depression speed of the accelerator pedal 52 Etc. are not reflected. Therefore, at the target gear stage GS ^* based on the shift line, the driving force F sufficient for the driver's expectation cannot be obtained, and the accelerator pedal 52 is further stepped on by the driver, so that a power-on downshift occurs continuously. Such a so-called busy shift may occur, and drivability may be reduced.

Therefore, in the present embodiment, when the power-on downshift of the automatic transmission 10 is determined as the accelerator opening Acc increases, the maximum driving force Fmax that can be generated after the power-on downshift is based on the accelerator opening Acc in advance. A gear that exceeds a predetermined threshold is determined as the target gear GS ^* of the downshift destination. That is, at the time of the power-on downshift of the automatic transmission 10, it is only the execution of the power-on downshift itself that is determined by the shift line, and the shift destination gear stage is not determined by the shift line, but the target gear stage GS. The gear stage of the speed change destination is determined based on a predetermined threshold value based on the maximum driving force Fmax at ^* and the accelerator opening Acc. This threshold is, for example, a predicted required driving force Freqp as an estimated value of the required driving force F expected in the immediate future when the driver depresses the accelerator pedal 52. Then, for example, among the gear stages in which the maximum driving force Fmax exceeds the predicted required driving force Freqp, the highest gear stage is determined as the target gear stage GS ^* .

More specifically, returning to FIG. 5, the predicted required driving force calculation unit, that is, the predicted required driving force calculation means 122 is, for example, the required driving force Freq, the differential value dFreq of the required driving force Freq, and the second floor of the required driving force Freq. Based on the differential value ddFreq, the predicted required driving force Freqp is calculated. FIG. 9 is a conceptual diagram when the predicted required driving force Freqp is calculated. In FIG. 9, the predicted required driving force Freqp at the time when the power-on downshift of the automatic transmission 10 is determined is obtained by adding the additional driving force request amount to the required driving force Freq. The required amount of additional driving force is expressed as an integral value from the time when the power-on downshift as shown by the hatched portion is determined in the required driving force differential value dFreq characteristic to the time when the rising of the required driving force Freq converges. . In the present embodiment, the required amount of additional driving force is not directly calculated, but is simply calculated as the estimated additional amount of required driving force ΔFreqp in order to simplify the calculation. This estimated additional driving force amount ΔFreqp is the area indicated by the shaded portion in the required driving force differential value dFreq characteristic, and is calculated based on the required driving force differential value dFreq and the required driving force second-order differential value ddFreq. Accordingly, the predicted required driving force calculating means 122 is based on the required driving force Freq, the required driving force differential value dFreq, and the required driving force second-order differential value ddFreq from the following equations (2) and (3) stored in advance, for example. To calculate the predicted required driving force Freqp.
Freqp = Freq + ΔFreqp (2)
ΔFreqp = (dFreq ² / ddFreq) × (1/2) (3)

The determination unit, that is, the determination unit 124 includes a downshift determination unit, that is, a downshift determination unit 126 that determines whether or not the downshift of the automatic transmission unit 10 is executed, and the downshift of the automatic transmission unit 10 that is executed is a power. A power-on determination unit that determines whether or not an on-down shift is performed, that is, a power-on determination unit 128, and a driving force comparison determination unit that compares the maximum driving force Fmax and the predicted required driving force Freqp at the target gear stage GS ^* . Force comparison judgment means 130.

The downshift determining unit 126 determines whether or not the downshift of the automatic transmission unit 10 is executed based on the target gear stage GS ^* determined by the target gear stage determining unit 114, that is, the target gear stage determining unit 114 It is determined whether or not the gear stage (GS-1) on the low speed side of the first gear stage is determined as the target gear stage GS ^{* with} respect to a gear stage different from the gear stage GS, that is, the actual gear stage GS currently running. In other words, the downshift determining means 126 indicates that the vehicle state represented by the actual accelerator opening degree Acc (or the required driving force Freq) and the vehicle speed V by the target gear stage determining means 114 is a shift diagram as shown in FIG. It is determined whether or not it is determined that the downshift line has been passed. The target gear stage determining means 114 determines the gear stage of the shift destination determined by passing through the upshift line as it is as the target gear stage GS ^* when the automatic transmission unit 10 is upshifted ^. At the time of downshift, the gear stage (GS-1) on the lower speed side of the actual gear stage GS that is currently traveling is changed to the temporary target gear stage GS ^* p (hereinafter referred to as the temporary target gear stage GS ^* p). ).

  The power-on determination means 128 determines whether or not the downshift when the downshift determination means 126 executes the downshift of the automatic transmission unit 10 is a power-on downshift, for example, the accelerator opening Acc. Is determined based on whether or not is greater than or equal to a predetermined accelerator opening Acc ′ set in advance for determining that the accelerator is on. Alternatively, the power-on determination means 128 may determine based on whether or not the accelerator opening Acc has increased as compared to before the downshift determination. That is, the power-on determination unit 128 may determine whether or not the downshift is caused by the increase in the accelerator opening Acc.

The maximum driving force calculating unit, that is, the maximum driving force calculating means 132 is based on the actual engine rotational speed _NE and the maximum throttle opening θ _TH (= 100%) from the engine torque map as shown in FIG. 8, for example. It calculates a maximum engine torque estimation value _{T E0} max as T _E max. Then, the maximum driving force calculating means 132, for example, from the relationship of the following equation (4) stored in advance, the temporary target gear stage based on the calculated maximum engine torque estimated value T _E0 max and the temporary target gear stage GS ^* p. The maximum driving force Fmax that can be generated in GS ^* p is calculated. Note that γGS ^* p is a gear ratio of the automatic transmission 10 at the temporary target gear stage GS ^* p.
_{Fmax = (T E0 max × γGS} * p × i × t) / r D ··· (4)

For example, when the power-on determining unit 128 determines the power-on downshift, the driving force comparison determining unit 130 determines that the predicted required driving force Freqp calculated by the predicted required driving force calculating unit 122 is the maximum driving force calculating unit 132. It is determined whether or not the calculated value is larger than the maximum driving force Fmax at the temporary target gear stage GS ^* p. That is, whether the predicted required driving force Freqp is whether within the maximum driving force Fmax at the temporary target gear GS * ^p, namely can achieve the predicted required driving force Freqp the temporary target gear GS * ^p Determine. Therefore, when the predicted required driving force Freqp is larger than the maximum driving force Fmax, the predicted required driving force Freqp cannot be achieved with the temporary target gear stage GS ^* p at that time.

Target gear determination unit 114, when the driving force comparison determination unit 130 by the prediction required driving force Freqp is determined to be greater than the maximum driving force Fmax at the temporary target gear GS * ^p is the temporary target gear GS ^* p Is set to the gear position on the lower speed side (temporary target gear stage GS ^* p−1). Then, the maximum driving force calculating means 132 calculates the maximum driving force Fmax at the new temporary target gear stage GS ^* p, and the driving force comparison determining means 130 calculates the calculated maximum driving force Fmax and the predicted required driving force Freqp. Compare. Thus, the target gear determination unit 114, the predicted required driving force Freqp sequentially is its temporary target gear GS * ^p while exceeding the maximum driving force Fmax that can be generated in the tentative target gear GS * ^p 1 The speed is set to the lower gear speed side (temporary target gear stage GS ^* p−1). On the other hand, if the target gear stage determining means 114 determines that the maximum driving force Fmax at the temporary target gear stage GS ^* p is greater than or equal to the predicted required driving force Freqp by the driving force comparison determining means 130, the target gear stage determining means 114 The target gear stage GS ^* p is determined as the target gear stage GS ^* . That is, the target gear position determining means 114, the provisional target gear GS * target the provisional target gear GS * ^p when the maximum driving force Fmax that can be generated is predicted required driving force Freqp above in ^p gear GS ^* Determine as.

By the way, apart from the busy shift described above, in the power-on downshift, the driving force F is increased by lowering (decreasing) the gear stage GS to the low vehicle speed side. At this time, the engine speed _NE is also increased at the same time. To do. Thus, the rise condition of the engine rotational speed N _E, that is, the target gear GS ^* determined as described above, the driver engine than joy that could ensure the required driving force Freq intended by the power-on downshift I feel strongly落過skill feeling of gear stage GS by the rise in the speed N _E, drivability may be lowered.

Accordingly, in this embodiment, further, calculates an estimated engine rotation speed variation .DELTA.N _E of the power-on downshift before and after the engine 30, determined in advance based on the accelerator opening Acc The larger the estimated engine rotation speed variation .DELTA.N _E as predicted required driving force Freqp as the threshold value that is is small, corrects the predicted required driving force Freqp based on the estimated engine rotation speed variation .DELTA.N _E. In other words, the larger the estimated engine rotation speed variation .DELTA.N _E, to reduce the predicted required driving force Freqp is to so relatively high vehicle speed side of the target gear GS ^* is determined. Thereby, the fall of gear stage GS is suppressed. Also, the larger the estimated engine rotation speed variation .DELTA.N _E, so feel stronger落過skill feeling gear GS, estimated engine rotation speed variation .DELTA.N _E exceeds a predetermined given variation .DELTA.N E _' In this case, the predicted required driving force Freqp may be corrected. Thereby, the drop of the gear stage GS is suppressed only when the estimated engine speed change amount ΔN _E exceeds the predetermined change amount ΔN _E ′. On the other hand, when the estimated engine rotation speed variation .DELTA.N _E is within a predetermined change amount .DELTA.N E _'is the driver intends (expected) power to a suitable gear GS to satisfy the required driving force Freq An on downshift is performed.

Specifically, the rotation speed change amount calculation unit, that is, the rotation speed change amount calculation means 134, for example, determines the actual engine rotation speed _NE and the target gear when the power-on determination means 128 determines the power-on downshift. Estimated engine speed N _E p (= γGS ^* p × N _OUT after power-on downshift to the temporary target gear stage GS ^* p set by the stage determining means 114, provided that the slip amount in the lockup clutch 34 is zero The estimated engine rotational speed change amount ΔN _E (= N _E p−N _E ) is calculated as an estimated value of the difference rotational speed from the above. The estimated engine rotation speed N _E p may be simply calculated as described above, but it is desirable in terms of accuracy to calculate it in consideration of the torque converter characteristics and the operating state of the lockup clutch 34.

Correction execution determination unit i.e. the correction process execution determining unit 136 determines whether the estimated engine rotation speed variation .DELTA.N _E calculated by the rotation speed variation amount calculating means 134 exceeds the predetermined change amount .DELTA.N E _'. This predetermined change amount ΔN _E ′ is, for example, an engine rotation speed change amount that is experimentally obtained and stored in advance to prevent the gear stage GS from dropping excessively so as not to feel the gear stage GS falling too strongly. It is a judgment value.

Correction processing unit i.e. the correcting means 138, when the correction execution determining unit 136 estimates engine rotation speed variation .DELTA.N _E is determined to exceed the predetermined variation .DELTA.N E _'is for example stored in advance following according to equation (5), converts the estimated engine rotation speed variation .DELTA.N _E by a predetermined constant K predetermined for rotation corresponding driving force F _{K (=} K × .DELTA.N _E), this rotation corresponding driving the predicted required driving force Freqp corrected by subtracting the force F _K, and calculates the predicted required driving force Freqpm corrected. When the predicted required driving force Freqp is corrected by the correction processing unit 138 and the corrected predicted required driving force Freqpm is calculated, the driving force comparison determination unit 130 calculates the maximum driving force Fmax and the corrected predicted value. The required driving force Freqpm is compared. The predetermined constant K is a predetermined constant stored previously obtained experimentally for converting the estimated engine rotation speed variation .DELTA.N _E to the driving force.
Freqpm = Freqp−K × ΔN _E (5)

  FIG. 10 illustrates a control operation for improving the drivability by determining an appropriate gear stage GS at the time of a power-on downshift accompanying an increase in the required amount of the vehicle by the driver, that is, a control operation of the electronic control device 100. It is a flowchart explaining the operation, and is repeatedly executed with a very short cycle time of, for example, about several milliseconds to several tens of milliseconds.

In FIG. 10, first, in step (hereinafter, step is omitted) S10 corresponding to the downshift determining unit 126, the target gear stage determining unit 114 changes the gear stage different from the current gear stage GS, that is, the actual gear currently being traveled. It is determined whether or not the gear stage (GS-1) on the lower vehicle speed side with respect to the stage GS is determined as the target gear stage GS ^* . That is, it is assumed that the vehicle state represented by the actual accelerator opening Acc (or the required driving force Freq) and the vehicle speed V has passed the downshift line in the shift diagram as shown in FIG. It is determined whether or not it has been determined. When the downshift determination of the automatic transmission unit 10 is made, the target gear stage determining means 114 temporarily sets the gear stage (GS-1) on the low speed side of the first gear relative to the actual gear stage GS currently being traveled. It is set as the target gear stage GS ^* p. If the determination in S10 is negative, this routine is terminated. If the determination is positive, in S20 corresponding to the power-on determination means 128, the determined downshift is performed when the determination in S10 is positive. Whether or not a power-on downshift due to the depression of the accelerator pedal 52 is determined based on, for example, the accelerator opening Acc. If the determination in S20 is negative, in S70 corresponding to the target gear stage determination means 114, the temporary target gear stage GS ^* p set in the downshift determination is determined as the target gear stage GS ^* . On the other hand, if the determination in S20 is affirmative, in S30 corresponding to the predicted required driving force calculation means 122, from the above equations (2) and (3), the required driving force Freq, the required driving force differential value dFreq, and The predicted required driving force Freqp is calculated based on the required driving force second-order differential value ddFreq.

Next, in S40 corresponding to the rotational speed change amount calculating means 134, the correction processing execution determining means 136, and the correction processing means 138, after a power-on downshift to the actual engine rotational speed _NE and the temporary target gear stage GS ^* p. the estimated engine rotational speed N _{E p} and the rotational speed difference of the estimated engine rotation speed variation .DELTA.N E as an estimate of the _{(= N E p-N E} ) is calculated. It is determined whether or not the calculated estimated engine speed change amount ΔN _E exceeds a predetermined change amount ΔN _E ′. If the estimated engine rotation speed variation .DELTA.N _E is determined to be greater than a predetermined change amount .DELTA.N E _'in accordance with the equation (5), the predicted required driving force Freqp estimated engine speed calculated by the S30 It is corrected on the basis of the speed variation .DELTA.N _E, namely the predicted required driving force Freqp is arbitrated by the estimated engine rotation speed variation .DELTA.N _E, predicted required driving force Freqpm after correction is calculated. On the other hand, if the estimated engine rotation speed variation .DELTA.N _E is determined to be within a predetermined change amount .DELTA.N E _'it is as it subsequent steps were calculated predicted required driving force Freqp is not corrected by the S30 Used.

Next, in S50 corresponding to the maximum driving force calculation means 132 and the driving force comparison determination means 130, for example, from the engine torque map as shown in FIG. 8, the actual engine speed _NE and the maximum throttle opening θ _TH (= 100%). ) the maximum engine torque estimation value T _E0 max is calculated as the maximum engine torque T _E max based, based formula (4 relationships) to its maximum engine torque estimation value T _E0 max and provisional target gear GS * ^p Thus, the maximum driving force Fmax that can be generated at the temporary target gear stage GS ^* p is calculated. Whether the predicted required driving force Freqp calculated in S30 or the corrected predicted required driving force Freqpm calculated in S40 is greater than the maximum driving force Fmax in the temporary target gear stage GS ^* p. Is determined. That is, it is determined whether or not the predicted required driving force Freqp (or the corrected predicted required driving force Freqpm) cannot be satisfied within the range of the maximum driving force Fmax at the temporary target gear stage GS ^* p.

If the determination in S50 is affirmative, in S60 corresponding to the target gear stage determination means 114, the temporary target gear stage GS ^* p is changed to the gear stage on the lower speed side (temporary target gear stage GS ^* p-1). The setting is changed, and S40 and subsequent steps are executed in the new temporary target gear stage GS ^* p. Thus, while the predicted required driving force Freqp (or the corrected predicted required driving force Freqpm) exceeds the maximum driving force Fmax that can be generated in the temporary target gear stage GS ^* p, the temporary target gear stage GS ^*. p is sequentially changed to the gear position on the lower vehicle speed side (temporary target gear stage GS ^* p−1). On the other hand, if the determination in S50 is negative, in S70 corresponding to the target gear stage determination means 114, the temporary target gear stage GS ^* p when S50 is negative, that is, within the range of the maximum driving force Fmax. The temporary target gear stage GS ^* p when it is determined that the predicted required driving force Freqp (or the corrected predicted required driving force Freqpm) can be satisfied is determined as the target gear stage GS ^* . Thus, the provisional target gear GS * ^p is the target when the maximum driving force Fmax that can be generated in the tentative target gear GS * ^p is the predicted required driving force Freqp (or predicted required driving force Freqpm corrected) or It is determined as the gear stage GS ^* .

As described above, according to the present embodiment, when a power-on downshift of the automatic transmission 10 associated with an increase in the required amount of the vehicle by the driver, for example, an accelerator stepping operation is determined, it can occur after the power-on downshift. Since the gear stage GS whose maximum driving force Fmax exceeds a predetermined threshold value based on the accelerator opening degree Acc is determined as the target gear stage GS ^* of the downshift destination, the drive that the driver intends (expects) A power-on downshift to an appropriate gear stage GS that satisfies the force Freq is performed. Therefore, the occurrence of a power-on downshift accompanying further depression of the accelerator pedal 52 is suppressed, and so-called busy shift is suppressed. Therefore, an appropriate gear is determined at the time of a power-on downshift accompanying an increase in the required driver amount, and the drivability can be suppressed and the drivability can be improved.

Further, according to this embodiment, the power-on downshift to calculate the estimated engine rotation speed variation .DELTA.N _E before and after the engine 30, the threshold value said predetermined higher the estimated engine rotation speed variation .DELTA.N _E is large is small maximum, because the threshold is corrected based on the estimated engine rotation speed variation .DELTA.N _E, the greater the estimated engine rotation speed variation .DELTA.N _E, after a power-on downshift exceeding the threshold as The driving force Fmax may be relatively small, and the gear stage GS on the higher vehicle speed side is determined as the target gear stage GS ^* of the downshift destination. In other words, the larger the estimated engine rotation speed variation .DELTA.N _E, it is suppressed that gear GS is too lowered to the low vehicle speed side. Therefore, an appropriate gear stage is determined at the time of a power-on downshift accompanying an increase in the driver request amount, and it is possible to improve the drivability by suppressing a feeling of excessive gear stage dropping.

Further, according to this embodiment, since the predetermined threshold is corrected when the estimated engine rotation speed variation .DELTA.N _E exceeds the predetermined change amount .DELTA.N E _', estimated engine rotation speed variation .DELTA.N _E The gear stage GS is suppressed from being lowered too much to the low vehicle speed side only when the engine speed is so large that it exceeds the predetermined change amount ΔN _E ′, that is, when the user feels that the gear stage GS is too weak. On the other hand, the driver intends (expects) when the estimated engine speed change amount ΔN _E is small enough to be within the range of the predetermined change amount ΔN _E ′, that is, when the gear stage GS does not feel too much. A power-on downshift to an appropriate gear stage that satisfies the required driving force Freq is performed.

Further, according to the present embodiment, the predetermined threshold is the predicted required driving force Freqp calculated based on the required driving force Freq, the required driving force differential value dFreq, and the required driving force second-order differential value ddFreq. Yes, among the gears where the maximum driving force Fmax exceeds the predicted required driving force Freqp, the highest gear is determined as the target gear GS ^* , so the power-on downshift accompanying an increase in the driver requirement In this case, an appropriate gear stage is determined without applying a great load.

Further, according to the present embodiment, when the downshift of the automatic transmission unit 10 is determined, the gear stage (GS-1) on the lower speed side of the actual gear stage GS that is currently running is the temporary target gear. It is set as a stage GS * ^p, while the predicted required driving force Freqp exceeds the maximum driving force Fmax that can be generated in the tentative target gear GS * ^p is the temporary target gear GS * ^p is successively 1-stage low When the maximum driving force Fmax that can be generated at the temporary target gear stage GS ^* p is equal to or higher than the predicted required driving force Freqp while being set to the vehicle speed side gear stage (temporary target gear stage GS ^* p-1) Since the temporary target gear stage GS ^* p is determined as the target gear stage GS ^* , a more appropriate gear stage can be determined without applying a large load during a power-on downshift accompanying an increase in the driver request amount. .

Further, according to the present embodiment, the estimated engine rotational speed change amount ΔN _E is converted into the rotation equivalent driving force F _K (= K × ΔN _E ) by a predetermined constant K, and the predicted required driving force Freqp is since the predicted required driving force Freqpm corrected by being subtracted by the rotation corresponding driving force F _K is calculated, at the time of power-on downshift accompanying the driver demand increase, a more appropriate落過skill feeling gear To be suppressed.

  As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.

  For example, in the above-described embodiment, the automatic transmission 10 is a stepped automatic transmission configured by a combination of operations of hydraulic friction engagement devices such as clutches or brakes. This is a synchronous mesh type parallel twin-shaft transmission well known as a manual transmission that includes a transmission gear between two shafts and selectively transmits one of a plurality of pairs of transmission gears by a synchronization device. However, it may be a synchronous mesh type parallel two-shaft automatic transmission whose gear stage can be automatically switched by a synchronizing device driven by a hydraulic actuator or the like. In short, if the automatic transmission 10 is a stepped automatic transmission in which a plurality of gear stages are selectively switched, the present invention can be applied. Further, the clutch or brake that is an engagement element of the automatic transmission 10 may be an electromagnetic engagement device such as an electromagnetic clutch or a magnetic powder clutch.

Further, a driving force related value may be used as the driving force of the vehicle in the above-described embodiment. This driving force-related value is a parameter that corresponds to the driving force F of the vehicle on a one-to-one basis, and includes not only the driving torque or driving force F at the driving wheels 46, but also the output torque T _OUT of the automatic transmission 10, Engine torque T _E , vehicle acceleration, torque on axle 44, torque T _IN on turbine shaft of torque converter 32, that is, input shaft 22 of automatic transmission 10, accelerator opening Acc (or throttle valve opening θ _TH , intake air the amount Q, the air-fuel ratio, the actual values such as the engine torque T _E that is calculated based fuel injection amount) and the engine rotational speed N _E, required to be calculated based on the accelerator opening Acc, etc. (target) engine torque T _E ^*, request the automatic transmission 10 (target) output torque _{T OUT} ^*, request (target) may be an estimate of such driving force Freq. Further, the actual drive torque or the like may be calculated from the engine torque _TE or the output torque T _OUT in consideration of the differential ratio, the radius of the drive wheel 46, or may be directly detected by, for example, a torque sensor or the like. The same applies to the other torques described above. Further, the required driving force Freq may be calculated based on, for example, the target gear stage GS ^* , the target engine torque T _E ^* , the target torque converter slip amount, and the like. The target engine torque T _E ^* may be calculated based on the vehicle speed V (the rotational speed N _OUT of the output rotating member 24), the turbine rotational speed _NT that is a function of the gear stage GS, and the accelerator opening Acc. .

Further, the maximum driving force Fmax in the above-described embodiment is calculated based on the maximum engine torque estimated value T _E0 max and the temporary target gear stage GS ^* p by the maximum driving force calculating means 132, but various other factors are used. You may calculate based on. For example, since the required driving force Freq is set with the vehicle speed V as one element in consideration of the running resistance, the maximum driving force Fmax is similarly set to 1 so that the running resistance is taken into account. It is good also as a basis of calculation as one element.

  The above description is only an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

8: Vehicle drive device 10: Stepped automatic transmission 100: Electronic control device (control device)

Claims (6)

A control device for a vehicle drive device that controls a shift of a stepped automatic transmission so as to obtain a required driving force-related value calculated based on a required amount for a vehicle by a driver,
When a power-on downshift of the stepped automatic transmission accompanying an increase in the required amount is determined, a maximum driving force-related value that can be generated after the power-on downshift is a predetermined threshold value based on the required amount A control device for a vehicle drive device, wherein a gear stage exceeding the upper limit is determined as a target gear stage to be downshifted. Calculate the estimated rotational speed change amount of the driving force source before and after the power-on downshift,
2. The control device for a vehicle drive device according to claim 1, wherein the threshold value is corrected based on the estimated rotational speed change amount so that the threshold value is reduced as the estimated rotational speed change amount is increased. .   The control device for a vehicle drive device according to claim 2, wherein the threshold value is corrected when the estimated rotational speed change amount exceeds a predetermined change amount. The threshold value is a predicted required driving force related value calculated based on the required driving force related value, a differential value of the required driving force related value, and a second order differential value of the required driving force related value,
4. The gear stage on the highest speed side among the gear stages in which the maximum driving force-related value exceeds the predicted required driving force-related value is determined as the target gear stage. 2. A control device for a vehicle drive device according to item 1. When the power-on downshift is determined, the gear stage on the lower vehicle speed side is set as the temporary target gear stage with respect to the actual gear stage currently running,
While the predicted required driving force-related value exceeds the maximum driving force-related value that can be generated in the temporary target gear stage, the temporary target gear stage is sequentially set to a gear stage on the lower vehicle speed side, The temporary target gear stage when the maximum driving force-related value that can be generated in the temporary target gear stage is equal to or greater than the predicted required driving force-related value is determined as the target gear stage. A control device for a vehicle drive device.   The estimated required driving force related value is corrected by converting the estimated rotational speed change amount into a rotation equivalent driving force related value according to a predetermined constant, and subtracting the rotation equivalent driving force related value. The control device for a vehicle drive device according to claim 4 or 5.

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