JP6576275B2 - Control device for automatic transmission - Google Patents

Description

  The present invention relates to a control device for an automatic transmission having a stepped transmission mechanism capable of switching a plurality of shift stages.

  Conventionally, in a stepped transmission that shifts from a predetermined shift stage to another shift stage, torque that increases the output torque of a travel drive source such as an engine during a shift to reduce shift shock that occurs when the clutch is replaced. 2. Description of the Related Art A control device for an automatic transmission that performs up is known (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 07-127490

However, if the output torque (hereinafter referred to as “drive source torque”) of the travel drive source before the shift is already high, the conventional control device may not be able to sufficiently reduce the shift shock that occurs during the shift.
That is, the state where the drive source torque is high is a state where the difference from the maximum output value of the drive source torque is small, and the torque increase allowance that can be increased during the shift is small. When the shift is performed in such a state, the torque increase allowance described above may be insufficient with respect to the torque increase amount of the drive source torque necessary for suppressing the shift shock. In this case, the shift shock cannot be reduced sufficiently.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a control device for an automatic transmission that can increase a torque-up allowance during a shift and reduce a shift shock.

In order to achieve the above object, a control device for an automatic transmission according to the present invention includes an automatic transmission and drive source torque control means.
The automatic transmission has a stepped transmission mechanism that is arranged between a travel drive source and drive wheels and that can switch a plurality of shift stages by fastening and releasing a plurality of fastening elements. The drive source torque control means controls the output torque of the travel drive source when a shift is requested.
Further, the drive source torque control means determines the output torque of the automatic transmission generated by the stepped transmission mechanism when shifting from the pre-shift speed to the post-shift speed based on the maximum output value of the output torque of the travel drive source. A drive source torque threshold value corresponding to the torque obtained by subtracting the decrease variation is set. When the stepped speed change mechanism is the pre-shift speed stage and the load torque for the travel drive source is greater than the drive source torque threshold, torque reduction is performed to reduce the output torque of the travel drive source below the load torque. In addition, when the stepped speed change mechanism performs a shift from the pre-shift speed to the post-shift speed during torque reduction, the torque reduction is canceled during this shift and the output torque of the travel drive source is directed to the load torque. Increase.

Therefore, in the present invention, the torque output is reduced if the output torque of the travel drive source is high (a state larger than the drive source torque threshold) before the stepped transmission mechanism is shifted. And the maximum output value can be prevented from becoming too small. That is, it is possible to increase the torque increase margin of the output torque of the travel drive source that is required at the time of shifting.
Then, when performing a shift of the stepped transmission mechanism, the torque down is canceled during the shift, and the output torque of the travel drive source is increased toward the load torque. For this reason, it is possible to suppress the fluctuation of the output torque of the automatic transmission that occurs during the shift, and to reduce the shift shock.

It is a whole block diagram which shows the engine vehicle by which the automatic transmission to which the control apparatus of Example 1 was applied was mounted. It is a block diagram which shows the electronic control system of the automatic transmission to which the control apparatus of Example 1 was applied. It is a shift map figure which shows an example of the shift map stored in the memory | storage device of the integrated controller of Example 1. FIG. 3 is a flowchart illustrating a flow of a shift engine torque control process executed in the first embodiment. It is explanatory drawing which shows the setting method of the engine torque regulation value at the time of the torque reduction in the 2nd gear stage. It is explanatory drawing which shows the setting method of the engine torque regulation value at the time of torque reduction in the 1st gear stage. 6 is a time chart showing characteristics of an accelerator opening, an engine torque, a load torque, a through transmission ratio, a variator transmission ratio, an auxiliary transmission ratio, and a vehicle G when downshifting is performed in an automatic transmission of a comparative example. Accelerator opening, engine torque regulation value, engine torque, load torque, through gear ratio, variator gear ratio, auxiliary gear ratio, vehicle G when downshifting is performed in an automatic transmission to which the control device of the first embodiment is applied. It is a time chart which shows a characteristic. Accelerator opening, engine torque regulation value, engine torque, load torque, through gear ratio, sub gear ratio, variator gear ratio, when upshifting in the sub gear of the automatic transmission to which the control device of the first embodiment is applied 3 is a time chart showing each characteristic of a vehicle G. It is explanatory drawing which shows the other 1st example of a torque down method. It is explanatory drawing which shows the other 2nd example of the torque down method. It is explanatory drawing which shows the other 3rd example of the torque down method.

  Hereinafter, a mode for carrying out an automatic transmission control device of the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
The control device for an automatic transmission in the first embodiment is applied to an engine vehicle equipped with a continuously variable transmission with a sub-transmission. Hereinafter, the configuration of the control apparatus for the automatic transmission according to the first embodiment will be described by dividing it into “an overall system configuration”, “a shift control configuration based on a shift map”, and “a shift engine torque control processing configuration”.

[Overall system configuration]
FIG. 1 shows the overall configuration of an engine vehicle equipped with an automatic transmission to which the control device of the first embodiment is applied, and FIG. 2 shows an electronic control system of the automatic transmission. Hereinafter, based on FIG.1 and FIG.2, the whole system structure of the control apparatus of Example 1 is demonstrated.

A vehicle equipped with the automatic transmission 4 according to the first embodiment includes the engine 1 as a travel drive source.
The output rotation from the engine 1 is transmitted to the drive wheels 7 via the torque converter 2 with a lock-up clutch, the first gear train 3, the automatic transmission 4, the second gear train 5, and the final reduction gear 6.
The second gear train 5 is provided with a parking mechanism 8 that mechanically locks the output shaft of the automatic transmission 4 so that it cannot rotate during parking. In addition, the vehicle includes an oil pump 10 that is driven using a part of the power of the engine 1, and a hydraulic control circuit 11 that regulates the hydraulic pressure from the oil pump 10 and supplies the hydraulic pressure to each part of the automatic transmission 4. An engine controller 12 that outputs a command to a throttle valve actuator or the like built in the engine 1 to control the engine operating point, and an integrated controller 13 that controls the hydraulic control circuit 11 and the engine controller 12 are provided. Each configuration will be described below.

The automatic transmission 4 includes a variator 20 (a continuously variable transmission mechanism) and a sub transmission 30 (a stepped transmission mechanism) provided in series with the variator 20. This is called a “stage transmission”.
Here, “provided in series” means that the variator 20 and the auxiliary transmission 30 are provided in series in the same power transmission path. The input shaft of the sub-transmission 30 may be directly connected to the output shaft of the variator 20 as in the first embodiment, or may be connected via another speed change or power transmission mechanism (for example, a gear train or a clutch). It may be. Further, the input shaft of the variator 20 may be connected to the output shaft of the auxiliary transmission 30.

  The variator 20 is a belt-type continuously variable transmission mechanism that includes a primary pulley 21, a secondary pulley 22, and a V-belt 23 that is wound around the pulleys 21 and 22. Each of the pulleys 21 and 22 includes a fixed conical plate, a movable conical plate that is arranged with a sheave surface facing the fixed conical plate and forms a V-groove between the fixed conical plate, and the movable conical plate. The hydraulic cylinders 23a and 23b are provided on the back surface of the movable cylinder to displace the movable conical plate in the axial direction. When the hydraulic pressure supplied to the hydraulic cylinders 23a and 23b is adjusted, the width of the V groove changes, the contact radius between the V belt 23 and each pulley 21 and 22 changes, and the transmission ratio of the variator 20 changes steplessly. .

  The auxiliary transmission 30 is a stepped transmission mechanism with two forward speeds and one reverse speed. The sub-transmission 30 is connected to a Ravigneaux type planetary gear mechanism 31 in which two planetary gear carriers are coupled, and a plurality of rotating elements constituting the Ravigneaux type planetary gear mechanism 31, and a plurality of components that change their linkage state. A friction fastening element is provided. A low brake 32, a high clutch 33, and a reverse brake 34 are provided as friction engagement elements. When the supply hydraulic pressure to each of the frictional engagement elements 32 to 34 is adjusted and a changeover shift that changes the engagement / release state of each of the frictional engagement elements 32 to 34 is performed, the gear position of the auxiliary transmission 30 is changed.

  That is, if the low brake 32 is engaged and the high clutch 33 and the reverse brake 34 are released, the shift speed of the sub-transmission 30 is the first speed (starting speed). When the high clutch 33 is engaged and the low brake 32 and the reverse brake 34 are released, the shift speed of the sub-transmission 30 is the second speed (traveling speed) with a smaller gear ratio than the first speed. Further, when the reverse brake 34 is engaged and the low brake 32 and the high clutch 33 are released, the shift stage of the sub-transmission 30 becomes the reverse stage. Hereinafter, the state where the sub-transmission 30 is in the first speed is referred to as “low speed mode”, and the state where the sub-transmission 30 is in the second speed is referred to as “high speed mode”.

  The integrated controller 13 (drive source torque control means) manages the energy consumption of the entire vehicle and has the function of running the vehicle with the highest efficiency. As shown in FIG. 2, the CPU 131 and the RAM / ROM A storage device 132, an input interface 133, an output interface 134, and a bus 135 that connects them to each other.

  The input interface 133 includes an output signal of an accelerator opening sensor 41 that detects an accelerator opening APO, an output signal of a primary rotation speed sensor 42 that detects a primary rotation speed Npri of the variator 20 (an input rotation speed of the variator 20), An output signal of a transmission output rotational speed sensor 43 that detects an output rotational speed Nout of the auxiliary transmission 30 (an output rotational speed of the automatic transmission 4) is input. Further, the input interface 133 receives an output signal of an oil temperature sensor 44 that detects the ATF oil temperature of the automatic transmission 4, an output signal of an inhibitor switch 45 that detects the position of the select lever, and an output torque signal of the engine 1. An engine torque signal Te is input. Furthermore, the output signal of the secondary rotation speed sensor 46 that detects the secondary rotation speed Nsec of the variator 20 (the output rotation speed of the variator 20), the output signal of the engine rotation speed sensor 47 that detects the engine rotation speed Ne of the engine 1, and the torque converter An output signal from a turbine rotation speed sensor 48 that detects a turbine rotation speed Nt (input rotation speed of the automatic transmission 4) 2 is input.

  The storage device 132 stores a shift control program for the automatic transmission 4 and a shift map (see FIG. 3) used in the shift control program. The CPU 131 reads out and executes a shift control program stored in the storage device 132 and performs various arithmetic processes on various signals input via the input interface 133 to generate a shift control signal and a driving force control signal. The generated shift control signal is output to the hydraulic control circuit 11 via the output interface 134 and the generated driving force control signal is output to the engine controller 12 via the output interface 134. Various values used in the arithmetic processing by the CPU 131 and the arithmetic results are appropriately stored in the storage device 132.

  The hydraulic control circuit 11 has a plurality of flow paths and a plurality of hydraulic control valves. Based on the shift control signal from the integrated controller 13, the hydraulic control circuit 11 controls a plurality of hydraulic control valves to switch the hydraulic pressure supply path and prepares the necessary hydraulic pressure from the hydraulic pressure generated by the oil pump 10. This is supplied to each part of the automatic transmission 4. As a result, the gear ratio of the variator 20 and the gear position of the sub-transmission 30 are changed, and the automatic transmission 4 is shifted.

  The engine controller 12 outputs a command for controlling the operating point (Ne, Te) of the engine 1 to a throttle valve actuator or the like built in the engine 1 based on a drive torque control signal from the integrated controller 13. Thereby, the output torque of the engine 1 is changed.

[Shift control configuration by shift map]
FIG. 3 shows an example of a shift map stored in the storage device of the integrated controller. Hereinafter, a shift control configuration based on the shift map will be described with reference to FIG.

The operating point of the automatic transmission 4 is determined based on the vehicle speed VSP and the primary rotational speed Npri on the shift map shown in FIG. The vehicle speed VSP is obtained from the output rotational speed Nout of the auxiliary transmission 30 and the gear ratio in the second gear train 5 and the final reduction gear 6. The vehicle speed information obtained from the sensor signal from the wheel speed sensor may be input and used as the “vehicle speed VSP”.
In FIG. 3, the slope of the line connecting the operating point of the automatic transmission 4 and the zero point of the lower left corner of the transmission map is obtained by multiplying the transmission ratio of the automatic transmission 4 (the transmission ratio of the variator 20 by the transmission ratio of the sub-transmission 30). The total transmission ratio, that is, the overall transmission ratio of the automatic transmission 4 achieved by the variator 20 and the auxiliary transmission 30 (hereinafter referred to as “through transmission ratio”).
Similar to the shift map of the conventional belt type continuously variable transmission, a shift line is set for each accelerator opening APO, and the shift of the automatic transmission 4 is selected according to the accelerator opening APO. Is performed according to the shift line.

That is, the integrated controller 13 refers to the shift map and sets the through speed ratio corresponding to the vehicle speed VSP and the accelerator opening APO (operating point) as the “arrival through speed ratio”.
The “reaching through speed ratio” is a target value that the through speed ratio should finally reach in the operating state. Then, the integrated controller 13 sets a “target through speed ratio”, which is a transient target value for causing the through speed ratio to follow the attained through speed ratio with a desired response characteristic, and sets the variator 20 and the sub-transmission 30 to Control is performed to perform “cooperative shifting” that matches (follows) the actual through speed ratio with the target through speed ratio.

  When “cooperative shifting” is performed, first, a target sub-transmission ratio in the sub-transmission 30 is calculated. Here, if the sub-transmission 30 does not shift, the target sub-speed ratio is a speed ratio realized at the first speed stage or a speed ratio realized at the second speed stage. If the sub-transmission 30 shifts, the input rotational speed and the output rotational speed of the sub-transmission 30 are calculated according to the progress state of the shift, and the target sub-transmission ratio is calculated from the calculated values.

  When the target sub-speed ratio is calculated, the target through speed ratio is divided by the calculated target sub-speed ratio, and this divided value is set to the target speed ratio of the variator 20 (hereinafter referred to as “target variator speed ratio”). Then, shift control of the variator 20 is performed so that the transmission ratio of the variator 20 matches (follows) the target variator transmission ratio. As a result, the target variator speed ratio is controlled in accordance with the target sub-speed ratio so that the through speed ratio follows the target value.

  For simplicity, FIG. 3 shows a full load line (shift line when accelerator opening APO = 8/8), partial line (shift line when accelerator opening APO = 4/8), coast line ( Only the shift line when the accelerator opening APO = 0) is shown.

  When the automatic transmission 4 is in the low speed mode, the automatic transmission 4 uses the low speed mode lowest line obtained by maximizing the transmission ratio of the variator 20 and the low speed mode maximum obtained by minimizing the transmission ratio of the variator 20. It is possible to shift between the High line. At this time, the operating point of the automatic transmission 4 moves in the L region and the M region. On the other hand, when the automatic transmission 4 is in the high speed mode, the automatic transmission 4 has the maximum high speed mode low line obtained by maximizing the transmission ratio of the variator 20 and the high speed mode maximum High obtained by minimizing the transmission ratio of the variator 20. The speed can be changed between the lines. At this time, the operating point of the automatic transmission 4 moves in the M region and the H region.

  The “L region” is a region surrounded by the low-speed mode lowest line and the high-speed mode lowest line. The “M region” is a region surrounded by the high-speed mode lowest line and the low-speed mode highest line. The “H region” is a region surrounded by the low-speed mode highest line and the high-speed mode highest line.

  Further, the gear ratio of each gear stage of the sub-transmission 30 is such that the gear ratio corresponding to the low speed mode highest line (low speed mode highest high gear ratio) corresponds to the high speed mode lowest line (high speed mode lowest gear shift). Ratio). Thus, a low speed mode ratio range that is a range of the through transmission ratio of the automatic transmission 4 that can be taken in the low speed mode and a high speed mode ratio range that is a range of the through transmission ratio of the automatic transmission 4 that can be taken in the high speed mode are Partially overlap. When the operating point of the automatic transmission 4 is in the M region (overlapping region) sandwiched between the high-speed mode lowest line and the low-speed mode highest line, the automatic transmission 4 can select either the low-speed mode or the high-speed mode. It has become.

  Further, on the shift map, the mode switching up shift line (upshift line 1 → 2 up shift line of the sub-transmission 30) for performing the up-shift of the sub-transmission 30 is lower than the low-speed mode highest line. The position is set to (large). Further, on the shift map, a mode switching down shift line (2 → 1 down shift line of the sub-transmission 30) for performing the down shift of the sub-transmission 30 is higher than the high-speed mode lowest line (speed ratio). (Small).

  When the operating point of the automatic transmission 4 crosses the mode switching up shift line or the mode switching down shift line, that is, when the target through speed ratio of the automatic transmission 4 changes across the mode switching speed ratio. Or the mode switching speed ratio, the integrated controller 13 performs mode switching speed control. In the case of performing “cooperative shifting” during the mode switching shift control, the integrated controller 13 responds to the target transmission ratio of the sub-transmission 30 so that the actual through transmission ratio follows the target through transmission ratio (target value). The gear ratio of the variator 20 is controlled. Specifically, the speed ratio of the variator 20 is set to a value obtained by dividing the target through speed ratio by the speed ratio of the auxiliary transmission 30.

[Engine torque control processing configuration during shifting]
FIG. 4 is a flowchart showing the flow of a shift engine torque control process executed in the first embodiment. Hereinafter, each step of FIG. 4 representing the engine torque control process at the time of shifting according to the first embodiment for controlling the output torque of the engine 1 at the time of executing the shift of the auxiliary transmission will be described. Note that the flowchart shown in FIG. 4 starts when the engine 1 is turned on and is repeated until the engine 1 stops.

In step S1, it is determined whether or not the shift stage of the sub-transmission 30 is in the second speed stage and is in the drive travel state. If YES (sub-transmission = second speed drive), the process proceeds to step S2. If NO (sub-transmission ≠ second speed drive), the process proceeds to step S11.
Here, “drive travel” refers to travel in a state where torque is output from the engine 1, and is determined to be drive travel when the accelerator pedal is depressed (accelerator opening APO> 0). Further, whether or not the speed is the second speed is determined based on the engagement / release state of the frictional engagement element in the auxiliary transmission 30.

In step S2, following the determination that the sub-transmission = second speed drive in step S1, it is determined whether or not the accelerator opening APO of the engine 1 is greater than or equal to a first predetermined value set in advance. If YES (APO ≧ first predetermined value), the process proceeds to step S3. If NO (APO <first predetermined value), the process proceeds to step S10.
Here, the “accelerator opening APO” is obtained from the output signal of the accelerator opening sensor 41 and indicates the load torque Te ^* for the engine 1. The “first predetermined value” is an accelerator opening threshold at which the load torque Te ^* for the engine 1 becomes a “first drive source torque threshold _{T_th1} ” to be described later. The “first drive source torque threshold T _{_th1} ” refers to the maximum output value Te _{_MAX} of the output torque of the engine 1 (hereinafter referred to as “engine torque Te”), when the sub-transmission 30 is in the second speed (pre-shift speed). This is a value corresponding to the torque obtained by subtracting the variation _{ΔT_AT_down} of the output torque of the automatic transmission 4 that occurs during the inertia phase of the downshift (shift) from the first gear to the first gear (shifted gear). That is, when the accelerator opening APO becomes equal to or greater than the “first predetermined value”, it is determined that the load torque Te ^* for the engine 1 is higher than the first drive source torque threshold _{T_th1} .
It should be _{noted that} “a decrease fluctuation amount _{ΔT_AT_down} of the output torque of the automatic transmission 4 generated during the inertia phase of the downshift from the second gear to the first gear of the auxiliary transmission 30” is obtained in advance by an experiment or the like.

In step S3, following the determination that APO ≧ first predetermined value in step S2, the torque reduction is set during execution _assuming that the load torque Te ^* for the engine 1 is higher than the first drive source torque threshold _{T_th1.} An engine torque regulation value (hereinafter referred to as “downtime regulation value”) is calculated, and the process proceeds to step S4.
Here, the “down time regulation value (= engine torque regulation value set during torque reduction)” is a value smaller than the load torque Te ^* applied to the engine 1 that appears at the accelerator opening APO. In this step S3, first, a maximum output value _{Te_MAX} of the engine torque Te obtained from the current engine speed Ne is obtained using a torque map that defines the relationship between the engine speed Ne and the engine torque Te. Then, from the maximum output value _{Te_MAX} of the engine torque Te, a torque increase amount necessary for torque increase executed when the sub-transmission 30 is downshifted (torque increase required to reduce a shift shock due to deceleration occurring during the downshift) Set to the value obtained by subtracting the cost.
Here, the maximum output value Te _{_MAX} engine torque Te, the sub transmission 30 is reduced fluctuation ΔT of the output torque of the automatic transmission 4 that occur during the inertia phase of the downshift to the first speed from the second speed stage _{_AT_down Is} set to a value _obtained by adding or subtracting the output torque fluctuation ( _{ΔT_cvt_UP} , _{ΔT_cvt_down} ) of the automatic transmission 4 caused by the shift of the variator 20 performed during the downshift of the sub-transmission 30 to the value obtained by subtracting. To do.
That is, the regulation value at the time of down is set to the first drive source torque threshold value _{T_th1,} and the fluctuation amount (ΔT of the output torque of the automatic transmission 4 generated by the shift of the variator 20 performed during the shift of the sub-transmission 30. _{_cvt_UP} , ΔT _{_cvt_down} ).

The variator 20 is shift-controlled according to the target sub-transmission ratio so that the target through speed ratio follows the target value when the sub-transmission 30 is shifted, but in the case of upshifting, the output torque of the automatic transmission 4 Decreases and the output torque of the automatic transmission 4 increases when downshifting.
Therefore, when the shift state of the variator 20 is estimated and the sub-transmission 30 is in the second speed and the variator 20 is _upshifted , the down-time regulation value is changed from the first drive source torque threshold _{T_th1} to the variator upshift. The output torque fluctuation amount _{ΔT_cvt_UP} of the automatic transmission 4 is set to a value obtained by subtracting, and further torque reduction is performed. Further, when the auxiliary transmission 30 is in the second speed and the variator 20 is downshifted, the downtime regulation value is set to the output torque fluctuation of the automatic transmission 4 accompanying the variator downshift with _respect to the first drive source torque threshold _{T_th1.} Set to a value _obtained by adding the minute _{ΔT_cvt_down} to suppress the torque down.
FIG. 5 is an explanatory diagram showing an image of the calculation method of the down regulation value in step S3.

In step S4, following the calculation of the down time restriction value in step S3, the engine torque restriction value is set to the down time restriction value calculated in step S3, and the process proceeds to step S5.
As a result, the output upper limit of the engine 1 is regulated to a value lower than the load torque Te ^* for the engine 1, and torque reduction is performed to reduce the engine torque Te below the load torque Te ^* .

In step S5, following execution of torque reduction in step S4, it is determined whether or not a shift request from the second speed to the first speed, that is, a downshift request, has occurred for the auxiliary transmission 30. If YES (2 → 1 shift requested), the process proceeds to step S6. If NO (2 → 1 shift requested), the process returns to step S2.
Here, the presence / absence of a shift request from the second speed to the first speed is determined based on the operating point of the automatic transmission 4 on the shift map shown in FIG.

In step S6, following the determination that there is a 2 → 1 shift request in step S5, the sub-transmission 30 is downshifted, and it is determined whether or not the inertia phase of this downshift has started. If YES (inertia phase start), the process proceeds to step S7. If NO (before inertia phase starts), step S6 is repeated.
Here, in the “downshift inertia phase”, the subtransmission ratio (transmission ratio of the subtransmission 30) calculated from the input / output rotation of the subtransmission 30 changes from the second gear ratio to the first gear ratio. It is a phase. Therefore, it is determined that the “inertia phase” has started when the auxiliary transmission ratio starts to increase from the second gear ratio.

In step S7, following the determination of the start of the inertia phase in step S6, the engine 1 torque reduction performed in step S4 is cancelled, and the increase slope (increase rate of change) of the engine torque regulation value is calculated. Proceed to step S8.
Here, "cancellation of the torque-down", the load torque Te ^* engine torque Te which is lower than is to gradually increase in towards the load torque Te ^* over a period of time. Specifically, the engine torque regulation value is increased over a certain time from the down regulation value calculated in step S4, and is matched with the load torque Te ^* .
Further, the “increasing slope of the engine torque regulation value” is an increasing change speed at which the engine torque regulation value is changed from the down regulation value to a value matching the load torque Te ^* over the inertia phase time in step S7. It is. Thereby, when the inertia phase ends, the output upper limit of the engine 1 matches the load torque Te ^* , and the engine torque Te matches the load torque Te ^* .
In the automatic transmission 4, during the inertia phase of the shift of the sub-transmission 30, the variator 20 is shift-controlled according to the change of the sub-speed ratio so that the through speed ratio follows the target value. Therefore, the inertia phase time is determined according to the shift time of the variator. That is, in step S7, the “increasing slope of the engine torque regulation value” is calculated based on the shift time of the variator 20 that is executed in accordance with the inertia phase.

In step S8, following the cancellation of torque reduction in step S7 and the calculation of the increase slope of the engine torque restriction value, the engine torque restriction value is increased with the increase slope calculated in step S7, and the process proceeds to step S9. .
Here, since the upper limit of the output of the engine 1 is gradually increased by increasing the engine torque regulation value, the engine torque Te substantially increases toward the load torque Te ^* .

In step S9, following the increase in engine torque Te in step S8, it is determined whether or not the downshift inertia phase of the auxiliary transmission 30 has ended. If YES (end of inertia phase), the process proceeds to step S10, and if NO (continuance of inertia phase), the process returns to step S8.
Here, the “inertia phase” is determined to end when the auxiliary transmission ratio reaches the first gear ratio.

In step S10, following the determination of the end of the inertia phase in step S9, etc., torque reduction is not performed, and the process proceeds to return.
Here, the “torque-down non-execution state” is to set the engine torque restriction value that restricts the output upper limit of the engine 1 to a predetermined value that is larger than the maximum output value _{Te_MAX} of the engine torque Te. As a result, the engine torque Te is not substantially limited and can be output so as to coincide with the load torque Te ^* .

In step S11, following the determination that the sub-transmission is not the second speed drive in step S1, it is determined whether or not the gear position of the sub-transmission 30 is the first speed stage and is in the drive travel state. If YES (subtransmission = first speed drive), the process proceeds to step S12. If NO (subtransmission ≠ first speed drive), the process proceeds to return.
Here, when the accelerator pedal is depressed (accelerator opening APO> 0), it is determined that the vehicle is traveling. Further, whether or not the gear is in the first speed is determined based on the engagement / release state of the friction engagement element in the auxiliary transmission 30.

In step S12, it is determined whether or not the accelerator opening APO of the engine 1 is equal to or larger than a second predetermined value set in advance following the determination that the sub-transmission = first speed drive in step S11. If YES (APO ≧ second predetermined value), the process proceeds to step S13. If NO (APO <second predetermined value), the process proceeds to step S10.
Here, the “accelerator opening APO” is obtained from the output signal of the accelerator opening sensor 41. The “second predetermined value” is an accelerator opening threshold at which the load torque Te ^* for the engine 1 becomes a “second drive source torque threshold _{T_th2} ” described later. The “second drive source torque threshold _{T_th2} ” is _determined from the maximum output value _{Te_MAX} of the engine torque Te, and the sub-transmission 30 _changes from the first gear (the gear before shifting) to the second gear (the gear after shifting). This is a torque value corresponding to the torque obtained by subtracting the decrease variation _{ΔT_AT_up} of the output torque of the automatic transmission 4 that occurs during the torque phase of the upshift (shift). That is, when the accelerator opening APO becomes equal to or greater than the “second predetermined value”, it is determined that the load torque Te ^* for the engine 1 is higher than the second drive source torque threshold _{T_th2} .
It should be _{noted that} “a decrease variation _{ΔT_AT_up} of the output torque of the automatic transmission 4 that occurs during the torque phase of the upshifting of the sub-transmission 30 from the first gear to the second gear” is obtained in advance by experiments or the like.

In step S13, following the determination of APO ≧ second predetermined value in step S12, the down time regulation value is calculated assuming that the load torque Te ^* for the engine 1 is higher than the second drive source torque threshold _{T_th2.} Proceed to S14.
Here, the “down time regulation value” is a value smaller than the load torque Te ^* for the engine 1 that appears at the accelerator opening APO, as in step S3. In this step S13, from the maximum output value _{Te_MAX} of the engine torque Te, the amount of decrease in the output torque of the automatic transmission 4 that occurs during the torque phase of the upshift from the first gear to the second gear of the sub-transmission 30. _Set to a value obtained by subtracting _{ΔT_AT_up} . That is, the down-time restriction value when the sub-transmission 30 is in the first speed is set to the second drive source torque threshold _{T_th2} .
Note that, during the upshift torque phase of the sub-transmission 30, the variator 20 maintains a substantially constant gear ratio. Therefore, it is not necessary to consider the correction due to the shift of the variator 20 in the down-time regulation value when the auxiliary transmission 30 is upshifted.
FIG. 6 is an explanatory diagram showing an image of the calculation method of the down time regulation value in step S13.

In step S14, following the calculation of the down time restriction value in step S13, the engine torque restriction value is set to the down time restriction value calculated in step S13, and the process proceeds to step S15.
As a result, the output upper limit of the engine 1 is regulated to a value lower than the load torque Te ^* for the engine 1, and torque reduction is performed to reduce the engine torque Te below the load torque Te ^* .

In step S15, following execution of torque reduction in step S14, it is determined whether or not a shift request from the first gear to the second gear, that is, an upshift request has occurred for the auxiliary transmission 30. If YES (1 → 2 shift requested), the process proceeds to step S16. If NO (1 → 2 shift requested), the process returns to step S12.
Here, the presence / absence of a shift request from the first gear to the second gear is determined based on the operating point of the automatic transmission 4 on the shift map shown in FIG.

In step S16, following the determination that there is a 1 → 2 shift request in step S15, the sub-transmission 30 is upshifted, and it is determined whether or not the torque phase of this upshift has started. If YES (start of torque phase), the process proceeds to step S17. If NO (before torque phase starts), step S16 is repeated.
Here, the “upshift torque phase” reduces the hydraulic pressure supplied to the disengagement side frictional engagement element (low brake 32) and increases the hydraulic pressure supplied to the engagement side frictional engagement element (high clutch 33). Is a phase in which the shift stage responsible for transmitting the shift from the first speed to the second speed. At this time, since the sub-transmission ratio does not change, this “torque phase” is the pre-shift preparation phase of the sub-transmission 30 (the hydraulic pre-charge is applied to the high clutch 33 which is the engagement side frictional engagement element, and this high clutch It is determined that the process has been started when the phase of waiting for 33 in a state immediately before fastening is completed.

In step S17, following the determination of the start of the torque phase in step S16, the torque reduction of the engine 1 performed in step S14 is cancelled, and the increase slope (increase rate of change) of the engine torque regulation value is calculated. Proceed to step S18.
Here, "cancellation of the torque-down", as in step S7, that the engine torque Te which is lower than the load torque Te ^*, gradually increasing over a period of time toward the load torque Te ^* It is.
Further, the “increasing slope of the engine torque regulation value” is equal to the load torque Te ^* from the down regulation value calculated in step S13 by taking the torque phase time over the engine torque regulation value in this step S17. It is the increasing rate of change that changes to a value. Thereby, when the torque phase ends, the output upper limit of the engine 1 matches the load torque Te ^* , and the engine torque Te matches the load torque Te ^* .
In the automatic transmission 4, the variator 20 is controlled to shift during the inertia phase of the shift of the sub-transmission 30. Therefore, the torque phase time is determined according to the state of the sub-transmission 30 regardless of the shift time of the variator. That is, in step S17, the “increasing slope of the engine torque regulation value” is calculated based on the torque phase time of the upshift of the auxiliary transmission 30.

In step S18, following the cancellation of torque reduction in step S17 and the calculation of the increase slope of the engine torque restriction value, the engine torque restriction value is increased with the increase slope calculated in step S17, and the process proceeds to step S19. .
Here, since the upper limit of the output of the engine 1 is gradually increased by increasing the engine torque regulation value, the engine torque Te substantially increases toward the load torque Te ^* .

In step S19, following the increase in engine torque Te in step S18, it is determined whether or not the upshift torque phase of the auxiliary transmission 30 has ended. If YES (end of torque phase), the process proceeds to step S10, and if NO (torque phase continued), the process returns to step S18.
Here, it is determined that the “torque phase” is finished when the inertia phase starts, that is, when the auxiliary transmission ratio starts to change from the first gear ratio.

Next, the operation will be described.
First, “control of automatic transmission of comparative example and its problems” will be described. Subsequently, the operation in the first embodiment will be described separately for “down-shift engine torque control operation” and “up-shift engine torque control operation”.

[Control of automatic transmission of comparative example and its problems]
FIG. 7 is a time chart showing the characteristics of accelerator opening, engine torque, load torque, through speed ratio, variator speed ratio, auxiliary speed ratio, and vehicle G when downshifting is performed in the automatic transmission of the comparative example. . Hereinafter, based on FIG. 7, the control of the automatic transmission of the comparative example and its problem will be described.

  In the continuously variable transmission with a sub-transmission of the comparative example, when the accelerator pedal is depressed, the operating point on the shift map shown in FIG. 3 moves and the variator 20 is down-shifted, and then the sub-transmission 30 is lowered. May shift.

That is, when a downshift request the variator 20 at time t ₁ point in FIG. 7 occurs, adjusts the hydraulic pressure supplied hydraulic cylinder 23a of the variator 20, the 23b, downshift the variator 20 so variator transmission ratio becomes larger To do. Thereby, the through gear ratio also starts to increase. On the other hand, when the accelerator pedal is depressed, the accelerator opening APO increases, and the load torque Te ^* for the engine 1 appearing at the accelerator opening APO increases. Therefore, the engine torque Te increases as the load torque Te ^* increases. As a result, the acceleration (vehicle G) acting on the vehicle increases as the variator 20 shifts and the engine torque Te increases.

At time t ₂ time, the down-shift request of the sub transmission 30 occurs, performs a pressure precharge to low brake 32 which is the engagement side frictional engagement element, to wait the low brake 32 in engagement state immediately before preparation Start the phase.

At time t ₃ the time, when the preparation phase is completed, smoothly changing the subtransmission ratio to 1 gear ratio from the second speed gear ratio. At this time, the variator 20 is shifted in accordance with the change in the auxiliary transmission ratio so that the through transmission ratio follows the target value. Here, the variator 20 is upshifted at the same change speed according to the increase in the sub-transmission ratio, and the variator transmission ratio and the sub-transmission ratio are controlled in the opposite directions, so that the through speed of the sub-transmission 30 before and after the inertia phase is increased. Suppress changes in gear ratio.

  However, when the variator 20 is upshifted, the output torque of the automatic transmission 4 decreases, and the acceleration (vehicle G) acting on the vehicle decreases. Further, in the auxiliary transmission 30, the acceleration (vehicle G) acting on the vehicle decreases due to the inertia torque associated with the replacement from the high clutch 33 to the low brake 32. Further, in order to prevent the engine speed from blowing up when the clutch is replaced, if the clutch capacity is made close to the interlock that both the high clutch 33 and the low brake 32 are fastened, it further acts on the vehicle. The acceleration (vehicle G) decreases.

  As a result, the vehicle temporarily decelerates (the portion surrounded by the broken line A in FIG. 7) despite the driver's intention to accelerate, and a shift shock (hereinafter referred to as “pull shock”) due to deceleration occurs. The driver may feel uncomfortable.

On the other hand, it is considered to reduce the pulling shock by increasing the output of the engine 1 by increasing the output of the engine torque Te and increasing the output torque of the automatic transmission 4.
However, as in the comparative example shown in FIG. 7, as a result of increasing the engine torque Te according to the increase in the load torque Te ^* for the engine 1, the engine torque Te becomes high before the sub-transmission 30 is downshifted. _Therefore , there is almost no difference between the engine torque Te and the maximum output value _{Te_MAX} of the engine torque Te at the timing (time t ₃ ) when the pulling shock occurs. Therefore, the torque increase cost of the engine torque Te is reduced, and the pulling shock due to the torque increase of the engine 1 cannot be sufficiently reduced.

[Engine torque control during downshift]
FIG. 8 shows the accelerator opening, the engine torque regulation value, the engine torque, the load torque, the through speed ratio, the variator speed ratio, 4 is a time chart showing characteristics of an auxiliary transmission ratio and a vehicle G. Hereinafter, based on FIG. 8, the engine torque control action at the time of downshift of Example 1 is demonstrated.

In the vehicle of the first embodiment, when the auxiliary transmission 30 of the automatic transmission 4 is traveling in the state where the accelerator pedal is depressed at the second speed (APO> 0), step S1 → step S2 in the flowchart shown in FIG. Proceed to Time t ₁₁ and earlier shown in FIG. 8, the accelerator opening APO is less than the first predetermined value, the process proceeds to step S10, the non-execution state of the torque down of the engine 1. That is, the engine torque restriction value that restricts the output upper limit of the engine 1 is set to a predetermined value that is larger than the maximum output value _{Te_MAX of} the engine torque Te, and the engine torque Te is not substantially restricted, and the load torque Matches Te ^* .

At time t ₁₁ point shown in FIG. 8, to move the operating point on the shift map shown in FIG. 3 by the depression of the accelerator pedal, the downshift request is output to the variator 20, supply hydraulic cylinders 23a, 23b, The hydraulic pressure is adjusted, the variator gear ratio is increased, and the variator 20 starts downshifting. Thereby, the through gear ratio also starts to increase.

Further, when the accelerator pedal is depressed, the accelerator opening APO increases, and the load torque Te ^* for the engine 1 appearing at the accelerator opening APO increases. At this time, since the accelerator opening APO is less than a preset first predetermined value, the process proceeds from step S1 to step S2 to step S10, and the engine torque regulation value is _greater than the maximum output value _{Te_MAX} of the engine torque Te. It continues to be set to a large predetermined value.
For this reason, the output upper limit of the engine 1 is not substantially limited, and the engine torque Te increases as the load torque Te ^* increases. As a result, the acceleration (vehicle G) acting on the vehicle increases as the variator 20 shifts and the engine torque Te increases.

At time t ₁₂ when the accelerator opening APO reaches a first predetermined value, the process proceeds to step S2 → step S3 → step S4, downshift regulation value is calculated, at the time down to the engine torque restriction value is the calculated Set to the regulation value.
As a result, the output upper limit of the engine 1 is regulated to a value lower than the load torque Te ^* for the engine 1, and the engine torque Te is lower than the load torque Te ^* . As a result, the time t ₁₂ after the engine torque Te, the difference between the maximum output value Te _{_MAX} of the engine torque Te that is too small is prevented.

Since the variator 20 continues downshifting, the output torque of the automatic transmission 4 continues to increase and the vehicle G continues to increase due to the variator downshift. However, when the engine torque Te is lower than the load torque Te ^* , the acceleration (vehicle G) acting on the vehicle increases when the engine torque Te is increased in accordance with the load torque Te ^* (shown by a broken line in FIG. 8). As a result, the ascent speed of the vehicle G is moderated.

At time t ₁₃ the time, by the accelerator pedal is slowly depressed further, the operating point on the shift map is straddling the high speed mode Lowest Low line, downshift request of the sub transmission 30 occurs, the engagement side frictional engagement element The low-brake 32 is precharged with hydraulic pressure, and a preparation phase is started in which the low-brake 32 is kept in a state immediately before being engaged.
At this time, although the downshift request of the sub-transmission 30 has been output, the downshift inertia phase has not started, so the process proceeds from step S5 to step S6, and step S6 is repeated.
The sub-shift request of the sub-transmission 30 is an operation on the shift map because the vehicle speed decreases due to reaching an uphill although the accelerator pedal is in a high opening state and is not stepped on. It also occurs when a point crosses the high-speed mode lowest line.

Then, upon completion of preparation phase at time t ₁₄ the time, auxiliary transmission ratio is the speed ratio of the secondary transmission 30 starts to rise changed from the second speed gear ratio. As a result, assuming that the downshift inertia phase has started, the process proceeds from step S6 to step S7 to step S8. Then, the torque reduction of the engine 1 is released, and an increase slope (increase change speed) of the engine torque restriction value is calculated, and the engine torque restriction value increases with the calculated inclination.
That is, the time t ₁₄ will output upper limit of the engine 1 from time gradually increases, will substantially engine torque Te increases toward the load torque Te ^*.

  On the other hand, in the auxiliary transmission 30, when the clutch is changed over from the high clutch 33 that is the disengagement side frictional engagement element to the low brake 32 that is the engagement side frictional engagement element, Torque decreases. In addition, when the sub-transmission ratio changes, the variator 20 is shifted according to the change in the sub-transmission ratio so that the through transmission ratio follows the target value. The variator 20 is upshifted at a change rate of the order. The output torque of the automatic transmission 4 also decreases due to the upshift of the variator 20.

As described above, during the downshift inertia phase of the sub-transmission 30, the output torque of the automatic transmission 4 decreases due to the rotation change of the sub-transmission 30 and the upshift of the variator 20, but the engine torque Te is the load torque Te. Increase toward ^* . Therefore, a decrease in the output torque of the automatic transmission 4 that occurs when the auxiliary transmission 30 is downshifted is mitigated by an increase in the engine torque Te.
Further, from the time t ₁₂ time, has implemented a torque down of the engine 1, and prevents the difference between the engine torque Te, the maximum output value Te _{_MAX} of the engine torque Te becomes too small. As a result, it is possible to secure a torque-up allowance for the engine torque Te before the sub-transmission 30 is shifted, and to sufficiently increase the engine torque Te against a decrease in the output torque of the automatic transmission 4. it can.
As a result, the torque-up allowance during the downshift of the auxiliary transmission 30 is made larger than in the comparative example (see FIG. 7), and the reduction amount ΔT ₂ of the acceleration (vehicle G) acting on the vehicle The amount of decrease ΔT ₁ when not increasing (indicated by a broken line in FIG. 8) can be made smaller, and the pulling shock can be reduced.

Then, at time t ₁₅ the time, when the sub-gear ratio reaches the first gear ratio, it is determined that the inertia phase of the downshift is completed, the process proceeds to step S9 → step S10, the non-carried state of the torque down of the engine 1 It becomes. That is, the engine torque restriction value that restricts the output upper limit of the engine 1 is set to a predetermined value that is larger than the maximum output value _{Te_MAX} of the engine torque Te, and the engine torque is not substantially limited, and the load torque Te Matches ^* .

Thus, in the control device of the first embodiment, the accelerator opening APO becomes equal to or greater than the first predetermined value while the auxiliary transmission 30 is driving at the second speed, and the load torque Te ^* for the engine 1 is the drive source torque. When it becomes higher than the threshold value, the engine torque restriction value is set to the restriction value at the time of down, and the torque is reduced to reduce the engine torque Te.
If a request for downshifting of the sub-transmission 30 occurs during torque reduction, the torque reduction is canceled, the engine torque regulation value is increased, and the engine torque Te is increased toward the load torque Te ^* .

This prevents the difference between the output engine torque Te and the maximum output value _{Te_MAX} of the engine torque Te from being reduced before the downshift of the auxiliary transmission 30 is reduced. Torque up allowance during downshift can be increased. Further, when the sub-transmission 30 is downshifted, the engine torque Te can be increased to suppress a decrease in the output torque of the automatic transmission 4 that occurs during the downshift, thereby reducing a pulling shock.

Further, in the first embodiment, the down-time restriction value that is the engine torque restriction value set during the torque reduction of the engine 1 is _determined from the maximum output value _{Te_MAX} of the engine torque Te, so that the auxiliary transmission 30 is in the second speed. Automatic torque generated by the change _{ΔT_AT_down in} the output torque of the automatic transmission 4 that occurs during the inertia phase of the downshift from the first gear to the first gear, and the shift of the variator 20 that is performed during the downshift of the sub-transmission 30. It is set to a value obtained by subtracting the fluctuation amount of the output torque of the transmission 4.
As a result, the engine torque Te during the torque reduction is set to the first drive source torque threshold _{T_th1,} and the output torque of the automatic transmission 4 generated by the shift of the variator 20 performed during the shift of the sub-transmission 30. Correction is made based on the variation.

For this reason, before the sub-transmission 30 is downshifted, at least a torque up allowance of the engine torque Te corresponding to the decrease fluctuation amount _{ΔT_AT_down} of the output torque of the automatic transmission 4 accompanying the downshift of the sub-transmission 30 is secured. Can be kept.
Thereby, the torque increase amount of the engine torque Te performed at the time of the downshift of the auxiliary transmission 30 can be equivalent to the torque increase amount necessary for reducing the pulling shock, and the occurrence of the pulling shock can be sufficiently reduced. Can do.

In addition, the engine torque Te during the torque reduction is corrected based on the variation ( _{ΔT_cvt_UP} / _{ΔT_cvt_down} ) of the output torque of the automatic transmission 4 caused by the shift of the variator 20 performed during the shift of the sub-transmission 30. Thus, it is possible to suppress torque fluctuation due to the shift of the variator 20, and to reduce the pulling shock during the shift of the auxiliary transmission 30.

Further, in the first embodiment, torque reduction is performed at the timing when the accelerator opening APO becomes equal to or greater than the first predetermined value and the load torque Te ^* exceeds the first drive source torque threshold _{T_th1} . Then, at the start of the downshift inertia phase of the sub-transmission 30, the automatic transmission that generates the engine torque Te from the first drive source torque threshold _{T_th1} (the maximum output value _{Te_MAX of the} engine torque during the inertia phase) 4 is a correction value obtained by subtracting the decrease fluctuation amount _{ΔT_AT_down} of the output torque.

  As a result, the torque increase allowance of the engine torque Te can be secured at the start of the downshift inertia phase of the auxiliary transmission 30, and the engine torque Te during the downshift can be sufficiently increased. Thus, the pulling shock generated by the downshift can be sufficiently reduced.

Further, in the first embodiment, when the engine torque Te is increased toward the load torque Te ^* by canceling the torque down, the increase gradient (increase change speed) of the engine torque Te is set to decrease the sub-transmission 30. Calculation is performed according to the progress of the inertia phase of the shift, and the engine torque Te is made to coincide with the load torque Te ^* at the end of the inertia phase.

  As a result, the output torque of the automatic transmission 4 can always be increased during the downshift inertia phase period, and a decrease in the driving force that occurs during the inertia phase period can be appropriately suppressed. For this reason, the pulling shock accompanying the clutch replacement of the auxiliary transmission 30 can be suppressed with good timing.

[Up-shift engine torque control]
FIG. 9 shows the accelerator opening, the engine torque regulation value, the engine torque, the load torque, the through gear ratio, the sub gear ratio, 4 is a time chart showing characteristics of a variator gear ratio and a vehicle G. Hereinafter, based on FIG. 9, the engine torque control action at the time of the upshift of the first embodiment will be described.

In the vehicle of the first embodiment, when the sub-transmission 30 of the automatic transmission 4 is traveling in a state where the accelerator pedal is depressed at the first gear (APO> 0), step S1 → step S11 → Proceed to step S12. Time t ₂₁ before the shown in FIG. 9, the accelerator opening APO is equal to or less than the second predetermined value, the process proceeds to step S10, the non-execution state of the torque down of the engine 1. That is, the engine torque restriction value that restricts the output upper limit of the engine 1 is set to a predetermined value that is larger than the maximum output value _{Te_MAX of} the engine torque Te, and the engine torque Te is not substantially restricted, and the load torque Matches Te ^* .

At time t ₂₁ point shown in FIG. 9, to move the operating point on the shift map shown in FIG. 3 by the depression of the accelerator pedal, the downshift request is output to the variator 20, supply hydraulic cylinders 23a, 23b, The hydraulic pressure is adjusted, the variator gear ratio is increased, and the variator 20 is downshifted. Thereby, the through gear ratio also starts to increase.

Further, when the accelerator pedal is depressed, the accelerator opening APO increases, and the load torque Te ^* for the engine 1 appearing at the accelerator opening APO increases. At this time, since the accelerator opening APO is less than the preset second threshold value, the process proceeds from step S1, step S11, step S12, step S10, and the engine torque regulation value is the maximum output value _{Te_MAX} of the engine torque Te. It continues to be set to a predetermined value greater than.
For this reason, the output upper limit of the engine 1 is not substantially limited, and the engine torque Te increases as the load torque Te ^* increases. As a result, the acceleration (vehicle G) acting on the vehicle increases as the variator 20 shifts and the engine torque Te increases.

At time t ₂₂ when the accelerator opening APO reaches the second threshold value, the process proceeds to step S12 → step S13 → step S14, downshift regulation value is calculated, when down the engine torque regulation value is the calculated regulation Set to a value.
Thereby, the output upper limit of the engine 1 is regulated so as to be lower than the load torque Te ^* for the engine 1, and the engine torque Te is lower than the load torque Te ^* . As a result, the time t ₂₂ after the engine torque Te, the difference between the maximum output value Te _{_MAX} of the engine torque Te that is too small is prevented.

Since the variator 20 continues downshifting, the output torque of the automatic transmission 4 increases due to the variator downshift, and the vehicle G continues to rise. However, when the engine torque Te is lower than the load torque Te ^* , the acceleration (vehicle G) acting on the vehicle increases when the engine torque Te is increased in accordance with the load torque Te ^* (shown by a broken line in FIG. 9). As a result, the ascent speed of the vehicle G is moderated.

At time t ₂₃ the time, by the vehicle speed increases at high opening degree state of the accelerator pedal, the operating point on the shift map is straddling the speed mode Highest High line, upshift request of the sub transmission 30 occurs, the engagement side The high clutch 33 that is a frictional engagement element is precharged with hydraulic pressure, and a preparation phase is started in which the high clutch 33 waits in a state immediately before engagement.
At this time, although the upshift request of the auxiliary transmission 30 has been output, the torque phase of this upshift has not started, so the process proceeds from step S15 to step S16, and this step S16 is repeated.
The upshift request of the sub-transmission 30 is made when the accelerator pedal is released slowly while the accelerator pedal is in a high opening state, so that the operating point on the shift map crosses the low-speed mode highest line. Also occurs.

Then, When you are ready phase at the time t ₂₄ point in time, the process proceeds to step S16 → step S17 → step S18 as the torque phase to start. As a result, the torque reduction of the engine 1 is cancelled, and the increase slope (increase change speed) of the engine torque restriction value is calculated, and the engine torque restriction value increases at the calculated increase slope. That is, the time t will ₂₄ times increased output upper limit of the engine 1 gradually, will substantially engine torque Te increases toward the load torque Te ^*.
On the other hand, in the sub-transmission 30, the output torque from the sub-transmission 30 decreases with an upshift from the low brake 32 that is the disengagement side frictional engagement element to the high clutch 33 that is the engagement side frictional engagement element. The output torque of the transmission 4 decreases.

However, when the torque phase of the upshift of the auxiliary transmission 30, although the output torque of the automatic transmission 4 decreases from the first speed driving force corresponding to the second speed driving force equivalent, from the time t ₂₂ time, the torque of the engine 1 The engine torque Te is suppressed from increasing. Therefore, the fluctuation range of the output torque of the automatic transmission 4 that is reduced when the sub-transmission 30 is upshifted can be reduced, and a pulling shock can be suppressed.
Further, at this time, since the engine torque Te increases toward the load torque Te ^* , a decrease in the output torque of the automatic transmission 4 can be reduced by increasing the engine torque Te.
As a result, the decrease width of the acceleration (vehicle G) acting on the vehicle can be made smaller than the decrease width when the engine torque Te is not increased (indicated by a broken line in FIG. 9), and the pulling shock can be reduced.

At time t _25, when the acceleration (vehicle G) acting on the vehicle reaches the equivalent of the first speed driving force and the sub-transmission ratio starts to change from the first speed gear ratio, it is determined that the upshift torque phase has ended. Then, the process proceeds from step S19 to step S10, and the engine 1 is not in a torque-down state. That is, the engine torque regulation value that regulates the output upper limit of the engine 1 is set to a predetermined value that is larger than the maximum output value _{Te_MAX of} the engine torque Te, and the engine torque Te is not substantially limited, and the load torque Matches Te ^* .

Thus, in the control device of the first embodiment, even when the auxiliary transmission 30 is driving at the first speed, if the load torque Te ^* for the engine 1 becomes higher than the drive source torque threshold, the engine torque The regulation value is set to the regulation value at the time of down, and the torque is reduced to reduce the engine torque Te.
Then, when an upshift request for the auxiliary transmission 30 is generated during torque reduction, the torque reduction is canceled, the engine torque regulation value is increased, and the engine torque Te is increased toward the load torque Te ^* .

  As a result, an increase in engine torque Te can be suppressed before the sub-transmission 30 is upshifted. Further, when the sub-transmission 30 is upshifted, the engine torque Te can be increased to suppress a decrease in the output torque of the automatic transmission 4 that occurs during the upshift, thereby reducing a pulling shock.

Further, in the first embodiment, torque reduction is performed at the timing when the accelerator opening APO becomes equal to or greater than the second predetermined value and the load torque Te ^* exceeds the second drive source torque threshold _{T_th2} . Then, at the start of the upshift torque phase of the auxiliary transmission 30, the engine torque Te is changed from the second drive source torque threshold _{T_th2} (the maximum output value _{Te_MAX} of the engine torque Te to the automatic shift generated during the torque phase). (A value obtained by subtracting the variation _{ΔT_AT_up} of the output torque of the machine 4).

  As a result, when the torque phase of the upshift of the sub-transmission 30 is started, it is possible to secure a torque-up allowance for the engine torque Te and sufficiently increase the engine torque Te during the upshift. Thus, the pulling shock generated by the upshift can be sufficiently reduced.

Further, in the first embodiment, when the engine torque Te is increased toward the load torque Te ^* by canceling the torque reduction, the increase gradient (increase change speed) of the engine torque is changed to the upshift of the auxiliary transmission 30. And the engine torque Te is matched with the load torque Te ^* at the end of the torque phase.

  Thereby, the fall of the driving force which arises in a torque phase period can be suppressed appropriately. For this reason, the pulling shock accompanying the clutch replacement of the auxiliary transmission 30 can be suppressed with good timing.

Next, the effect will be described.
In the automatic transmission control apparatus according to the first embodiment, the following effects can be obtained.

(1) A stepped shift that is arranged between the travel drive source (engine 1) and the drive wheels 7 and can switch between a plurality of shift stages by engaging and releasing a plurality of engagement elements (low brake 32, high clutch 33). An automatic transmission comprising an automatic transmission 4 having a mechanism (sub-transmission 30) and drive source torque control means (integrated controller 13) for controlling the output torque of the travel drive source (engine 1) when a shift is requested. In the control device of
In the drive source torque control means (integrated controller 13), the stepped transmission mechanism (sub transmission 30) is shifted from the maximum output value _{Te_MAX} of the output torque (engine torque Te) of the travel drive source (engine 1). Corresponds to the torque obtained by subtracting the decrease variation _{ΔT_AT_down} of the output torque of the automatic transmission 4 that occurs in the shift (downshift) from the previous shift speed (second speed) to the post-shift speed (first speed). Set drive source torque threshold (first drive source torque threshold _{T_th1} ),
The stepped speed change mechanism (sub transmission 30) is the pre-shift speed stage (second speed stage), and the load torque Te ^* for the travel drive source (engine 1) is the drive source torque threshold value (first drive). A torque _lowering the output torque (engine torque Te) of the travel drive source (engine 1) to be lower than the load torque Te ^* , if higher than the source torque threshold _{T_th1} ),
When the stepped transmission mechanism (sub-transmission 30) performs a shift (downshift) from the pre-shift gear stage (second gear stage) to the post-shift gear stage (first gear stage) during the torque reduction, The torque reduction is canceled during the shift (downshift), and the output torque (engine torque Te) of the travel drive source (engine 1) is increased toward the load torque Te ^* .
As a result, it is possible to increase a torque increase margin at the time of shifting and to reduce a shift shock.

(2) The drive source torque control means (integrated controller 13) outputs the output torque (engine torque Te) of the travel drive source (engine 1) during the torque reduction to the drive source torque threshold (first drive source torque threshold). _{T_th1} ) The configuration is set below.
Thereby, in addition to the effect of (1), the torque-up amount of the engine 1 that is performed when the sub-transmission 30 is shifted (downshift) can be made equivalent to the torque-up amount necessary to reduce the pulling shock, The occurrence of pulling shock can be sufficiently reduced.

(3) The shift from the pre-shift speed (second speed) to the post-shift speed (first speed) of the stepped transmission mechanism (sub-transmission 30) is a downshift,
The drive source torque control means (integrated controller 13) is configured such that, at the start of the downshift inertia phase, the output torque (engine torque Te) of the travel drive source (engine 1) is the drive source torque threshold value (first The torque reduction is performed so as to be equal to or less than the driving source torque threshold _{T_th1} ).
As a result, in addition to the effect of (1) or (2), at the start of the inertia phase, it is possible to secure a torque increase allowance of the engine torque Te, and sufficiently increase the torque of the engine 1 during the downshift. The pulling shock accompanying the downshift can be sufficiently reduced.

(4) When the inertia phase of the downshift of the stepped transmission mechanism (sub-transmission 30) is started, the drive source torque control means (integrated controller 13) releases the torque down and the travel drive source ( The output torque (engine torque Te) of the engine 1) starts to increase toward the load torque Te ^*, and the increasing change rate of the output torque (engine torque Te) of the travel drive source (engine 1) is increased in the inertia phase. The calculation is made according to the progress, and the output torque (engine torque Te) of the travel drive source (engine 1) is made to coincide with the load torque Te ^* at the end of the inertia phase.
As a result, in addition to the effect of (3), the output torque of the automatic transmission 4 can always be increased during the downshift inertia phase during which the output torque of the automatic transmission 4 decreases, and the driving force generated during the inertia phase period is reduced. Can be suppressed.

(5) The automatic transmission 4 is arranged in series with the stepped transmission mechanism (sub-transmission 30), the gear ratio can be changed steplessly, and the automatic transmission 4 of the stepped transmission mechanism (sub-transmission 30) Having a continuously variable transmission mechanism (variator 20) that shifts during an inertia phase during shifting;
The drive source torque control means (integrated controller 13) outputs an output torque (engine torque Te) of the travel drive source (engine 1) during the torque reduction when the stepped transmission mechanism (sub-transmission 30) downshifts. ) For the output torque fluctuation ( _{ΔT_cvt_UP} / _{ΔT_cvt_down} ) of the automatic transmission 4 caused by the shift of the continuously variable transmission mechanism (variator 20) during the downshift of the stepped transmission mechanism (sub transmission 30). It was set as the structure correct | amended based on.
Thereby, in addition to the effect of (3) or (4), the torque fluctuation due to the shift of the variator 20 can be suppressed, and the pulling shock during the shift of the sub-transmission 30 can be reduced.

(6) Shifting from the pre-shift speed (first speed) to the post-shift speed (second speed) of the stepped transmission mechanism (sub-transmission 30) is an upshift;
The drive source torque control means (integrated controller 13) is configured such that the output torque (engine torque Te) of the travel drive source (engine 1) is the drive source torque threshold (second The torque reduction is performed so as to be equal to or less than the drive source torque threshold _{T_th2} ).
Thereby, in addition to the effect of (1) or (2), the torque increase allowance of the engine torque Te can be secured at the start of the torque phase, and the torque increase of the engine 1 during the upshift can be sufficiently increased. The pulling shock accompanying the upshift can be sufficiently reduced.

(7) When the upshift torque phase of the stepped transmission mechanism (sub-transmission 30) starts, the drive source torque control means (integrated controller 13) cancels the torque down and the travel drive source ( The output torque of the engine 1) (engine torque Te) starts to increase toward the load torque Te ^*, and the increasing change rate of the output torque (engine torque Te) of the travel drive source (engine 1) is increased in the torque phase. Calculation is performed according to the progress, and the output torque (engine torque Te) of the travel drive source (engine 1) is made to coincide with the load torque Te ^* at the end of the torque phase.
As a result, in addition to the effect of (6), the output torque of the automatic transmission 4 can always be increased during the upshift torque phase period during which the output torque of the automatic transmission 4 decreases, and the driving force generated during the torque phase period is reduced. Can be suppressed.

  As mentioned above, although the control apparatus of the automatic transmission of this invention was demonstrated based on Example 1, it is not restricted to these Examples about a concrete structure, It concerns on each claim of a claim Design changes and additions are allowed without departing from the scope of the invention.

  In the first embodiment, an example in which a stepped transmission mechanism having two forward speeds and one reverse speed is applied as the auxiliary transmission 30 is shown. However, the auxiliary transmission is not limited to a stepped transmission mechanism with two forward speeds and one reverse speed, and may be a stepped transmission mechanism capable of switching between three or more forward speeds.

Further, in the first embodiment, the engine transmission Te during torque reduction is set to the first drive source torque threshold _{T_th1} , and the automatic transmission 4 generated by the shift of the variator 20 performed during the shift of the auxiliary transmission 30 is performed. _Is corrected based on the output torque fluctuation ( _{ΔT_cvt_UP} / _{ΔT_cvt_down} ).
However, the present invention is not limited to this. For example, in an automatic transmission that does not include a variator, or when the variator is not _shifted during shifting of the sub-transmission, the down-time regulation value is set to a value that is equal to or less than the first drive source torque threshold _{T_th1.} However, no correction is necessary. Even in this case, the torque increase amount of the engine torque Te that the sub-transmission 30 can secure before the downshift is set as the decrease variation _{ΔT_AT_down} of the output torque of the automatic transmission 4 due to the downshift of the sub-transmission 30. It can be.
Therefore, the amount of torque increase during the downshift of the auxiliary transmission 30 can be equivalent to the amount of torque increase necessary for reducing the pulling shock, and the occurrence of the pulling shock can be reduced.

Further, in the first embodiment, the engine torque regulation value is set to the first drive source torque threshold T at the timing when the accelerator opening APO becomes equal to or greater than the first predetermined value and the load torque Te ^* exceeds the first drive source torque threshold _{T_th1.} The correction value is set to _{_th1} .
However, the engine torque Te may be set to the first drive source torque threshold _{T_th1} at the start of the downshift inertia phase of the sub-transmission 30. That is, as shown in FIG. 10A, the engine torque regulation value may be set to the first drive source torque threshold _{T_th1} at the timing when the downshift inertia phase of the auxiliary transmission 30 starts.
In this case, the engine torque Te is not substantially regulated until immediately before the start of the downshift inertia phase of the sub-transmission 30, so that the engine torque Te can be made to follow the load torque Te ^* , and the driver's drive The difference from the force demand can be reduced.

Further, as shown in FIG. 10B, when the accelerator opening APO becomes equal to or greater than the first predetermined value, the engine torque regulation value is gradually decreased, and the engine torque is started at the timing when the downshift inertia phase of the auxiliary transmission 30 is started. The regulation value may be _set to be the first drive source torque threshold _{T_th1} .
Even in this case, the engine torque Te up to the start of the inertia phase can be made relatively large, the engine torque Te can be made to follow the load torque Te ^* , and the driver feels uncomfortable. be able to. Further, since the engine torque regulation value is gradually limited, the reduction range of the acceleration (vehicle G) acting on the vehicle can be suppressed.

Further, in the first embodiment, the engine torque regulation value during the torque reduction is maintained at the correction value of the first drive source torque threshold _{T_th1} until the downshift inertia phase of the auxiliary transmission 30 starts. However, the present invention is not limited thereto, and as shown in FIG. 10C, the engine torque regulation value during torque reduction may be increased in accordance with, for example, a corrected load torque obtained by multiplying the load torque Te ^* by 0.9. That is, the down time regulation value may be set by the first drive source torque threshold _{T_th1} and the correction load torque selection Low.

  In the first embodiment, when the sub-transmission 30 performs a downshift, the torque reduction is canceled (increasing the engine torque Te toward the load torque) during the inertia phase period of the downshift, When the sub-transmission 30 performs an upshift, an example is shown in which the torque down is canceled during the torque phase period of the upshift. However, the present invention is not limited to this, and torque reduction may be canceled at least during a period during which the sub-transmission 30 is shifting. That is, the torque reduction is canceled during the entire period during which the sub-transmission 30 is shifting (from the start of the preparation phase to the end of the shift), or the torque reduction is also canceled during a certain period before and after the inertia phase and the torque phase. You may do.

Further, in the first embodiment, an example of determining whether or not the load torque Te ^* for the engine 1 is larger than the first and second drive source torque thresholds _{T_th1} and _{T_th2} with reference to the accelerator opening APO. Indicated. However, the present invention is not limited to this. For example, the determination may be made based on the throttle opening of the engine 1. Even in this case, if the throttle opening set according to the accelerator operation becomes larger than the throttle opening threshold corresponding to the first and second drive source torque thresholds _{T_th1} and _{T_th2} , the “load torque Te ^* ≧ First and second driving source torque thresholds _{T_th1} , _{T_th2} ”.

  Moreover, in Example 1, although the example which applies this control means to the vehicle provided only with the engine 1 as a traveling drive source was shown, it does not restrict to this. For example, the present invention can be applied to a hybrid vehicle having an engine and a travel motor as a travel drive source, or an electric vehicle using only the travel motor as a travel drive source.

1 Engine (traveling drive source)
4 automatic transmission 7 drive wheel 13 integrated controller (drive source torque control means)
20 Variator (continuously variable transmission mechanism)
21 Primary pulley 22 Secondary pulley 23 V belt 30 Subtransmission (stepped transmission mechanism)
32 Low brake (Friction engagement element)
33 High clutch (Friction engagement element)

Claims (7)

An automatic transmission having a stepped transmission mechanism arranged between a travel drive source and drive wheels and capable of switching a plurality of shift speeds by fastening and releasing a plurality of fastening elements, and an output of the travel drive source when a shift request is made A drive source torque control means for controlling torque, and an automatic transmission control device comprising:
The drive source torque control means outputs the output torque of the automatic transmission that is generated when the stepped transmission mechanism shifts from the pre-shift speed to the post-shift speed based on the maximum output value of the output torque of the travel drive source. Set the drive source torque threshold corresponding to the torque minus the fluctuation of
Torque that reduces the output torque of the travel drive source below the load torque when the stepped speed change mechanism is the pre-shift speed and the load torque for the travel drive source is higher than the drive source torque threshold. Do down,
When the stepped transmission mechanism performs a shift from the pre-shift gear to the post-shift gear during the torque reduction, the torque reduction is canceled during the gear shift, and the output torque of the travel drive source is increased. A control device for an automatic transmission, which increases toward the load torque. The control device for an automatic transmission according to claim 1,
The control device for an automatic transmission, wherein the drive source torque control means sets an output torque of the traveling drive source during the torque reduction to be equal to or less than the drive source torque threshold. In the control device for an automatic transmission according to claim 1 or 2,
Shifting from the pre-shift gear stage to the post-shift gear stage of the stepped transmission mechanism is a downshift,
The drive source torque control means performs the torque reduction so that the output torque of the travel drive source becomes equal to or less than the drive source torque threshold at the start of the downshift inertia phase. Machine control device. In the control device for an automatic transmission according to claim 3,
When the inertia phase of the downshift of the stepped transmission mechanism starts, the drive source torque control means releases the torque down and starts increasing the output torque of the travel drive source toward the load torque, An automatic change rate of the output torque of the travel drive source is calculated according to the progress of the inertia phase, and the output torque of the travel drive source coincides with the load torque at the end of the inertia phase. Transmission control device. In the control device for an automatic transmission according to claim 3 or 4,
The automatic transmission has a continuously variable transmission mechanism that is arranged in series with the stepped transmission mechanism, can change a transmission ratio steplessly, and shifts during an inertia phase during a shift of the stepped transmission mechanism;
When the stepped transmission mechanism is downshifted, the drive source torque control means converts the output torque of the travel drive source during the torque down to the speed of the continuously variable transmission mechanism during the downshift of the stepped transmission mechanism. A control apparatus for an automatic transmission, wherein the correction is performed based on a fluctuation amount of an output torque of the automatic transmission caused by the automatic transmission. In the control device for an automatic transmission according to claim 1 or 2,
Shifting from the pre-shift gear stage to the post-shift gear stage of the stepped transmission mechanism is an upshift,
The drive source torque control means performs the torque reduction so that the output torque of the travel drive source becomes equal to or less than the drive source torque threshold at the start of the upshift torque phase. Machine control device. The control apparatus for an automatic transmission according to claim 6,
When the upshift torque phase of the stepped transmission mechanism starts, the drive source torque control means releases the torque down and starts increasing the output torque of the travel drive source toward the load torque, An automatic change rate of the output torque of the travel drive source is calculated according to the progress of the torque phase, and the output torque of the travel drive source coincides with the load torque at the end of the torque phase. Transmission control device.