JP2009235974A - Control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for an automatic transmission capable of preventing generation of gear shift shock due to torque down control in a learning correction fluctuation zone, and meeting demand for stabilization of gear shifting quality by securing consistency of start timing of torque down control in a learning correction stable zone and start timing of inertia phase. <P>SOLUTION: This control device for the automatic transmission is provided with a gear shift pressure learning correction control means (Fig.3) determining and storing correction quantity of engagement command pressure to a friction element relating to gear shift based on a deviation state between actual physical quantity and target physical quantity, a gear shift torque down control means starting output of command temporally dropping torque of the engine 1 when inertia phase start estimation timing predetermined by time management comes during gear shifting, and a torque down change-over control means (Fig.4) prohibiting gear shift torque down control until it is determined that gear shift pressure learning correction is converging and executing gear shift torque down control when it is determined that gear shift pressure learning correction is converging. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a control device for an automatic transmission that performs shift torque down control for temporarily reducing torque of a drive source during shifting.

Conventionally, a hydraulic switch has been provided in a hydraulic circuit that supplies fastening pressure to a friction element that is fastened during gear shifting, with the objective of reducing engine shocks in a timely manner to alleviate shift shocks. The time when the hydraulic switch is turned on is set as the reference time from the start of the inertia phase to the start of the inertia phase, and when the timer measurement time from the reference time passes the predetermined time that the inertia phase is expected to start, the engine torque 2. Description of the Related Art There is known an automatic transmission control device that performs timer torque down control for starting output of a command for temporarily reducing the torque. (For example, refer to Patent Document 1).
JP 2004-270726 A

  However, in the conventional automatic transmission control device, the time from when the piston strokes to the engagement start position until the inertia phase is started varies depending on the hardware variation or aging of each automatic transmission product. Due to the influence of the above, it does not always become a fixed time even for the same shift type under the same conditions. For this reason, even if the torque-down control is started after a predetermined time has elapsed from the reference time detected by the hydraulic switch, a deviation occurs from the start timing of the inertia phase, causing a thrust shock or driving There was a problem of causing a force pull shock.

  The present invention has been made paying attention to the above-mentioned problem, and prevents the occurrence of a shift shock by torque-down control in the learning correction fluctuation range, the start timing of torque-down control and the start timing of inertia phase in the learning correction stable range. It is an object of the present invention to provide a control device for an automatic transmission that can meet the demand for stabilization of shift quality by ensuring the consistency of the transmission.

In order to achieve the above object, in the present invention, in a control device for an automatic transmission that achieves a plurality of shift stages by switching the engagement state of a friction element in order to transmit torque from a drive source to drive wheels.
A shift pressure learning correction control means for measuring a physical quantity representing a shift progress state at the time of the current shift, and correcting the engagement command pressure of the friction element at the next shift based on a deviation state between the actual physical quantity and the target physical quantity;
Shifting torque that starts outputting a command to temporarily reduce the torque of the drive source at the expected start timing of the inertia phase preset by time management during the shift transition period from the start of shifting to the end of shifting at the time of shifting Down control means;
The convergence of the shift pressure learning correction by the shift pressure learning correction control means is determined, and the torque down control by the shift torque reduction control means is prohibited until it is determined that the shift pressure learning correction has converged, and the shift pressure learning correction is performed. Torque down switching control means for executing torque down control by the shift torque down control means when it is determined that
It is provided with.

Therefore, in the control device for an automatic transmission according to the present invention, the convergence of the shift pressure learning correction by the shift pressure learning correction control means is determined in the torque down switching control means, and the shift pressure learning correction is converged. Until the determination is made, the shift torque down control for determining the start timing by time management is prohibited.
Therefore, in the learning correction fluctuation region where the shift pressure learning correction has not converged, the occurrence of the thrust shock and the pulling shock of the driving force due to the deviation of the start timing of the inertia phase and the start timing of the torque reduction is prevented.
Then, in the torque down switching control means, when the convergence of the shift pressure learning correction by the shift pressure learning correction control means is determined and it is determined that the shift pressure learning correction has converged, the shift torque that determines the start timing by time management Down control is executed.
Therefore, in the learning correction stability range where the shift pressure learning correction has converged, the start timing of the inertia phase is also stabilized, and consistency with the start timing of the shift torque down control by time management is ensured, and the shift is performed in the inertia phase. Since the excessive input torque to the machine is effectively suppressed, the gear can be shifted quickly in a short time while maintaining good gear shifting quality.
As a result, it is necessary to stabilize the transmission quality by preventing the occurrence of shift shock by torque down control in the learning correction fluctuation range and ensuring the consistency between the start timing of torque down control and the start timing of the inertia phase in the learning correction stable range. Can respond.

  Hereinafter, the best mode for realizing a control device for an automatic transmission according to the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
FIG. 1 is an overall view showing an integrated control system for an engine and an automatic transmission in an engine vehicle to which the control apparatus for an automatic transmission according to the first embodiment is applied. FIG. 2 is an upshift pattern diagram illustrating an example of an upshift shift line set in the automatic transmission control unit of the automatic transmission control apparatus according to the first embodiment.

  As shown in FIG. 1, an integrated control system for an engine and an automatic transmission to which the automatic transmission control device of the first embodiment is applied includes an engine 1 (drive source), a torque converter 2, an automatic transmission 3, and the like. A transmission output shaft 4, an engine torque control actuator 5, a control valve unit 6, an engine control unit 7, an automatic transmission control unit 8, and an intercommunication line 9 are provided.

  The engine 1 injects fuel according to the throttle opening of an electric throttle valve that opens and closes according to an accelerator operation amount, and rotationally drives the engine output shaft with engine torque according to the fuel injection amount. The engine 1 is provided with an engine torque control actuator 5, and when a torque down control signal is inputted from the engine control unit 7, the electric throttle valve is controlled in the closing direction in preference to the accelerator operation amount, and the fuel is controlled. Reduce engine output by reducing the injection amount.

  The torque converter 2 is installed between the engine 1 and the automatic transmission 3, and includes a pump impeller 21 connected to the engine output shaft, a turbine runner 22 connected to the automatic transmission input shaft, and a one-way clutch in the transmission case. 23, and a stator 24 provided through 23.

  The automatic transmission 3 shifts the input rotational speed from the turbine runner 22 of the torque converter 2 to a plurality of stages by changing the torque transmission path in the gear train (not shown), and the output rotational speed after the shift is changed to the transmission output shaft. 4 is transmitted to the drive system from the drive wheel. The automatic transmission 3 has a plurality of friction elements for connecting and fixing the rotating members of the gear train for each gear stage, such as an engagement friction element 31 at the time of upshift and a release friction element 32 at the time of upshift. The speed change operation is performed by changing the speed of the two friction elements. Further, the automatic transmission 3 is provided with a control valve unit 6 in which various valves (spool valves, solenoid valves, etc.), accumulators and the like for controlling hydraulic pressures to a plurality of friction elements at the time of shifting are centrally arranged.

  The engine control unit 7 is an electronic control unit that performs control of fuel injection by outputting control commands to various control actuators while inputting engine-related information. In the engine control unit 7, when a torque down command is input from the automatic transmission control unit 8, a torque down control signal corresponding to the torque down command is output to the engine torque control actuator 5.

  The automatic transmission control unit 8 is connected to the engine control unit 7 by an intercommunication line 9, and also includes a throttle opening sensor 10, a vehicle speed sensor 11, a turbine speed sensor 12, an accelerator operation amount sensor 13, and a hydraulic switch 14. , Necessary information is input from other sensors and switches 15.

  The hydraulic switch 14 is provided in a hydraulic circuit that supplies a fastening hydraulic pressure to the engagement friction element 31 at the time of upshift. When the piston stroke starts and transmission torque starts to be generated in the engagement friction element 31, the switch is turned on. enter.

  This automatic transmission control unit 8 uses a shift pattern (shift diagram) representing the shift characteristics of the automatic transmission, and the vehicle operating point (a point determined by the throttle opening and the vehicle speed) is downshifted on the shift pattern. When a line is crossed, a downshift command is issued, and when an upshift line is crossed, an upshift command is issued to perform shift control. For example, in the case of an upshift, an upshift pattern diagram as shown in FIG. 2 stored in advance in the automatic transmission control unit 8 is used as a shift diagram.

  Further, the engine control unit 7 and the automatic transmission control unit 8 are connected by the mutual communication line 9 so that the overall control of the engine 1 and the automatic transmission 3 is performed. That is, on the one automatic transmission control unit 8 side, when a predetermined engine torque down condition is satisfied during upshifting, engine torque down control is executed and a torque down command is output to the engine control unit 7. On the other engine control unit 7 side, torque down control for reducing the output torque of the engine 1 is performed based on the torque down command input from the automatic transmission control unit 8.

The automatic transmission control unit 8 executes timer torque down control and gear ratio torque down control as shift torque down control and timer learning correction control.
In the timer torque down control, a reference time is set between the output time of the shift start command and the start time of the inertia phase, and when the timer measurement time from the reference time passes a predetermined time, the torque of the engine 1 is reduced. Start outputting the command to temporarily lower.
The gear ratio torque down control starts outputting a command to temporarily reduce the torque of the engine 1 when a gear ratio change indicating the progress of the shift is confirmed during the shift.
The timer learning correction control measures the time required from the output start time of the shift start command to the start time of the inertia phase, and at the next shift based on the time difference between the timer measurement time from the shift start and the target time, Correct the fastening command pressure of the element.

  Further, the automatic transmission control unit 8 performs torque down switching control of timer torque down control and gear ratio torque down control. This torque down switching control determines the convergence of the shift pressure learning correction by the timer learning correction control, and executes the gear ratio torque down control until the shift pressure learning correction is determined to have converged. If it is determined that the correction has converged, timer torque down control is executed instead of gear ratio torque down control.

  FIG. 3 is a flowchart showing the flow of the timer learning correction control process executed by the automatic transmission control unit 4 in the automatic transmission control apparatus according to the first embodiment. Each step will be described below (shift pressure learning). Correction control means, timer learning correction control means).

  In step S301, for example, in FIG. 2, when the vehicle speed increases from the operating point E to the operating point F due to an increase in the vehicle speed, and an upshift gear shift command from the second speed to the third speed is output, the current hydraulic pressure command value P1 Is added to the hydraulic pressure command value P0 used in the previous upshift from the second speed to the third speed, and the process proceeds to step S302.

  In step S302, following calculation of the current hydraulic pressure command value P1 in step S301, the engine throttle opening TVO is read from the throttle sensor 7 as the engine load, and the process proceeds to step S303.

  In step S303, following the reading of the throttle opening TVO in step S302, the vehicle speed V from the vehicle speed sensor 11 is read, and the process proceeds to step S304.

  In step S304, following the reading of the vehicle speed V in step S303, for example, in a learning operation state in which a learning operation condition with high learning sensitivity is established such that the throttle opening TVO is equal to or less than the set opening and the vehicle speed V is equal to or less than the set vehicle speed. If YES (learned driving condition is satisfied), the process proceeds to step S305. If NO (learned driving condition is not satisfied), the process proceeds to the end.

In step S305, following the determination that the learning operation condition is satisfied in step S304, the AT oil temperature ATF is used and corresponds to the target piston stroke time required from the output time of the shift start command to the start time of the inertia phase. The target time Tt to be calculated is calculated, and the process proceeds to step S306.
Here, the target time Tt is calculated as the time for achieving a high-quality shift without shock or delay according to the throttle opening TVO, the vehicle speed V, the AT oil temperature ATF, etc. for each shift type.

  In step S306, following the calculation of the target time Tt in step S305, the timer time Tr, which is the actual piston stroke time required from the output time point of the shift start command to the start point of the inertia phase, is measured, and the process proceeds to step S307.

In step S307, following the measurement of the timer time Tr in step 306, a learning correction value ΔP is calculated using the following equation, and the process proceeds to step S308.
ΔP = k (Tr-Tt)
Here, k is a constant that determines the correction amount for the time difference. Note that an upper limit value and a lower limit value are set for each friction element in the learning correction amount ΔP.

In step S308, following the calculation of the learning correction amount ΔP in step S307, the hydraulic pressure command value P0 and the learning correction amount ΔP, which are the calculation information of the hydraulic pressure command value P1 at the next shift, correspond to the learning operation state of the storage area. It memorize | stores in a memory | storage part and transfers to an end.
Here, the storage area of the hydraulic pressure command value P0 and the learning correction amount ΔP includes, for example, a plurality of storage units by subdividing the area according to the learning operation state such as the shift type, the throttle opening TVO, the vehicle speed V, the AT oil temperature ATF, and the like. Is set in advance.

  FIG. 4 is a flowchart showing a flow of torque down switching control processing executed by the automatic transmission controller 8 of the first embodiment, and each step will be described below (torque down switching control means).

In step S401, it is determined whether or not upshift control is being performed. If YES (during upshift control), the process proceeds to step S402, and if NO (during no upshift control), the process proceeds to return.
Here, the determination during the upshift control is performed, for example, from the time when the upshift gear shift command is output until the time when the hydraulic pressure to the engagement friction element 31 during the upshift reaches the line pressure level.

  In step S402, following the determination that the upshift control is being performed in step S401, from the timer learning correction control side, a learning correction amount ΔP that is the same type as the current shift type and that corresponds to the shift operation state. The difference value (Tt−Tr) between the target time Tt and the timer time Tr is calculated from the learning correction amount ΔP, and the absolute value | Tt−Tr | of the difference value (Tt−Tr) is less than the predetermined value. If YES (| Tt−Tr | <predetermined value), the process proceeds to step S405. If NO (| Tt−Tr | ≧ predetermined value), the process proceeds to step S403 (learning). Correction convergence determination unit). The difference value (Tt−Tr) is calculated by the equation (Tr−Tt) = ΔP / k. Further, the predetermined value is set as a learning correction convergence determination threshold value that the timer time Tr approaches the target time Tt by experiencing learning correction, and the learning correction amount ΔP is also stable below the variation error.

  In step S403, following the determination that | Tt−Tr | ≧ predetermined value in step S402, transmission input rotational speed information from the turbine rotational speed sensor 12 and transmission output rotational speed information from the vehicle speed sensor 11 are obtained. Is used to calculate the gear ratio, which is the ratio of the input / output speed of the transmission, and the gear ratio change is calculated by differential processing that takes the difference between the gear ratio in the previous process and the gear ratio in the current process. It is determined whether the ratio change amount exceeds a predetermined amount. If YES (gear ratio change amount> predetermined amount), the process proceeds to step S404. If NO (gear ratio change amount ≦ predetermined amount), the process returns. Transition.

  In step S404, following the determination that the gear ratio change amount in step S403> predetermined amount, or the determination in step S407 that the timer value> predetermined value, the torque down command (for example, the engine torque is set to 30). The engine torque down control is executed to output to the engine control unit 7 and the process proceeds to return.

  In step S405, following the determination that | Tt−Tr | <predetermined value in step S402, it is determined whether or not the hydraulic switch 14 is ON. If YES (hydraulic switch ON), the process proceeds to step S406. If NO (hydraulic switch OFF), return to return.

  In step S406, following the determination that the hydraulic switch 14 is ON in step S405, the timer value is counted up, and the process proceeds to step S407.

In step S407, following the count-up of the timer value in step S406, it is determined whether the timer value after the hydraulic switch 14 is turned on exceeds a predetermined value, and YES (timer value> predetermined value) is determined. If YES (NO in step S404), the process advances to return.
Here, the predetermined value is set as the time from when the hydraulic switch 14 is turned on until the inertia phase is started, and this predetermined value is also changed in the same manner as the target time Tt in the timer learning correction control. The optimum value is set according to the type, throttle opening TVO, vehicle speed V, AT oil temperature ATF, etc.

  The flow from step S405 → step S406 → step S407 to step S404 corresponds to the timer torque down control means, and the flow from step S403 to step S404 corresponds to the gear ratio torque down control means.

Next, the operation will be described.
First, “the reason why the timer torque down control needs to be stabilized” will be described, and then the operation of the control device for the automatic transmission according to the first embodiment will be described as “timer learning correction control operation”, “learning correction fluctuation range”. The gear ratio torque down control action in "and the timer torque down control action in the learning correction stable range" will be described separately.

[Reason for stabilization in timer torque down control]
FIG. 5 shows the characteristics of the gear ratio, the engine torque, and the output shaft torque when the start timing of the inertia phase is earlier than the start timing of the timer torque down control because the engagement hydraulic pressure is higher than the optimum pressure during upshifting. It is a time chart. FIG. 6 is a time chart showing the characteristics of the gear ratio, engine torque, and output shaft torque when the start timing of the inertia phase is later than the start timing of the timer torque down control because the engagement hydraulic pressure is lower than the optimum pressure during upshifting. It is a chart.

  The timer torque down control device is provided with a hydraulic switch in a hydraulic circuit that supplies a fastening pressure to a friction element that is fastened at the time of upshifting, and between the time when a shift start command is output and the time when an inertia phase starts, FIG. 5 and FIG. As shown in FIG. 6, the time point when the hydraulic switch is turned on is set as the reference time Tp, and the timer value, which is the measurement time from the reference time Tp, is set to the time point Td when a predetermined time Ts is predicted to start the inertia phase. Then, output of a command for temporarily reducing the engine torque TRD is started.

  However, the time required from the reference time Tp at which the piston strokes to the fastening start position to the time Ti at which the inertia phase starts is affected by hardware variations and changes over time of each automatic transmission product. Even with the same shift type under the same conditions, it does not always take a fixed time. For this reason, even if the torque-down control is started at a time Td when a predetermined time Ts elapses from the reference time Tp detected by the hydraulic switch, it is between the time Ti that is the start timing of the inertia phase. Deviation occurs.

  First, at the time of upshifting, an extra driving force is generated due to the moment of inertia of the engine 1, and an extra torque is generated during the inertia phase during shifting. By reducing the amount of extra torque generated in this inertia phase, the gear quality is improved, and the excess heat generated by the friction element that is fastened by upshifting is suppressed, improving the durability of the friction element. The engine torque down control is performed with the aim of achieving this.

  On the other hand, for example, when the engagement hydraulic pressure is higher than the optimum pressure at the time of upshifting, as shown in FIG. 5, the time Ti of the start timing of the inertia phase is earlier than the time Td of the start timing of the timer torque down control. In this case, since the engine torque TRD does not decrease even after the inertia phase is started, the input torque to the transmission becomes excessive during the start delay time ΔT1 of the timer torque down control. For this reason, as shown in the output shaft torque characteristics of FIG. 5, a thrust shock occurs due to excessive torque from the start of the inertia phase until the engine torque TRD decreases.

  For example, when the engagement hydraulic pressure is lower than the optimum pressure during upshifting, as shown in FIG. 6, the inertia phase starts when the time Ti of the start timing of the inertia phase is delayed from the time Td of the start timing of the timer torque down control. Since the engine torque TRD is reduced prior to the start of the operation, the input torque to the transmission becomes too low during the start preceding time ΔT2 of the timer torque down control. For this reason, as shown in the output shaft torque characteristics of FIG. 6, during the period from when the engine torque TRD decreases until the inertia phase starts, a pulling shock of the driving force occurs due to the torque being insufficient.

  As described above, in the timer torque down control, when the engagement hydraulic pressure is deviated from the optimum pressure during the upshift, the time Ti of the start timing of the inertia phase does not coincide with the time Td of the start timing of the timer torque down control, and the timer Since executing the torque down control may deteriorate the speed change quality, it is necessary to stabilize the timer torque down control by some measures.

[Timer learning correction control action]
FIG. 7 shows output torque, gear ratio change rate, gear ratio, and upshift engagement in an upshift transition period (an example of a shift transition period) in order to explain timer learning correction control in the automatic transmission control apparatus according to the first embodiment. It is a time chart which shows each characteristic of oil pressure command.

  When the learning driving condition is satisfied during traveling, the process proceeds from step S301 to step S302, step S303, step S304, step S305, step S306, step S307, and step S308 in the flowchart of FIG. 3. In step S307, ΔP = k The learning correction amount ΔP is calculated using the formula (Tr−Tt).

  That is, when the start of the inertia phase (= inertia phase) is late with respect to the target time Tt, and Tr> Tt, the previous hydraulic pressure command value P0 shown by the solid line characteristic in FIG. 7 is set to k (Tr−Tt). In order to make the timer time Tr as close as possible to the target time Tt at the next upshift, the change is made as shown by the one-dot chain line characteristic of FIG.

  On the other hand, when the inertia phase starts earlier than the target time Tt and Tr <Tt, the previous hydraulic pressure command value P0 shown by the solid line characteristics in FIG. 7 is decreased by k (Tr−Tt), As shown by the dotted line characteristics in FIG. 7, the timer time Tr is made as close as possible to the target time Tt at the next upshift.

  As described above, in the first embodiment, the timer learning correction control method is adopted as the learning correction method for correcting the variation in the engagement hydraulic pressure at the time of shifting for each friction element. For this reason, the engagement hydraulic pressure at the time of upshift is brought close to the optimum value, and the piston stroke time (shift time) of the friction element from the start of the shift to the start of the inertia phase can be managed so as to be maintained at a substantially constant time. it can. As a result, by accumulating experience of timer learning correction control, it is possible to achieve a shift quality that achieves both prevention of delayed shift feeling and reduction of shift shock during upshifting.

[Gear ratio torque down control action in learning correction fluctuation range]
FIG. 8 shows the gear ratio (Gr), engine torque (TRD), release pressure (P _OUT ), and gear ratio in the gear ratio torque down control executed in the learning correction fluctuation range in the automatic transmission control device of the first embodiment. 4 is a time chart showing characteristics of a fastening pressure (P _IN ) and an output shaft torque (T _OUT ).

  In the learning correction fluctuation region in which the upshift control is being performed and the difference absolute value | Tt−Tr | between the target time Tt and the timer time Tr is equal to or greater than a predetermined value, step S401 → step S402 → step in the flowchart of FIG. The process proceeds to S403, and while it is determined in step S403 that the gear ratio change amount ≦ the predetermined amount, the flow of proceeding from step S401 to step S402 to step S403 is repeated. When it is determined in step S403 that the gear ratio change amount> predetermined amount, the flow from step S403 to step S404 → return is repeated, and in step S404, a torque down command is output to the engine control unit 7. . When the change in the gear ratio is completed and it is determined again in step S403 that the gear ratio change amount is equal to or less than the predetermined amount, the flow from step S401 to step S402 to step S403 is repeated.

  Here, the learning correction fluctuation range in which the difference absolute value | Tt−Tr | between the target time Tt and the timer time Tr is equal to or greater than a predetermined value is, for example, when there is little shifting experience and the timer learning correction control has not converged, or In the learning operation state that has experienced shifting but has not experienced in the past, such as extremely low oil temperature, etc., or a disturbance is input to the shifting hydraulic control system, the shifting electronic control system, the shifting hardware mechanism system, etc. There are times, etc.

  Then, in the upshift control and in the learning correction fluctuation range, the gear ratio torque down control is executed as shown in FIG. In this gear ratio torque down control, the inertia phase is started at the timing of time Ti after the standby phase and the torque phase have elapsed from the output time T0 of the upshift shift start command. When the inertia phase starts, the gear ratio Gr starts to decrease. When it is determined that the gear ratio change amount> predetermined amount at the time Td, the engine torque TRD starts to decrease, and the gear ratio change amount ≦ location The decrease in engine torque TRD is maintained until it is determined that the amount is constant.

Therefore, the engagement pressure (P _IN ) characteristic of the friction element that is engaged during the upshift increases from the start point Ti of the inertia phase to the decrease start point Td of the engine torque TRD by the gradient RA2, and the decrease start point of the engine torque TRD. From Td until the gear ratio Gr becomes the gear ratio after the shift, the speed increases with a gentler gradient RA3 than the gradient RA2. And looking at the characteristics of the output shaft torque (T _OUT ), from the start point Ti of the inertia phase to the decrease start point Td of the engine torque TRD, there is a slight push-up shock due to the delay of the engine torque decrease timing, but it is temporarily learned Compared to the case where torque down control is not executed at all in the correction fluctuation region, the fluctuation range of the output shaft torque is suppressed to be small, and the shift quality is improved. Also, in the gear ratio torque down control, the start timing of the torque down control is always delayed from the start timing of the inertia phase. And it does not give a sense of incongruity due to a shock.

[Timer torque down control action in the learning correction stable range]
FIG. 9 shows the gear ratio (Gr), engine torque (TRD), release pressure (P _OUT ), and engagement in timer torque down control executed in the learning correction stable region in the automatic transmission control device of the first embodiment. 3 is a time chart showing characteristics of pressure (P _IN ) and output shaft torque (T _OUT ).

  In the learning correction stable range in which the upshift control is being performed and the difference absolute value | Tt−Tr | between the target time Tt and the timer time Tr is less than a predetermined value, step S401 → step S402 → step in the flowchart of FIG. Proceeding to S405, while the hydraulic switch 14 is OFF in step S405, the flow of going from step S401 to step S402 to step S405 to return is repeated. Then, when the hydraulic switch 14 is turned on in step S405, the process proceeds from step S405 to step S406 → step S407. While the timer value is equal to or smaller than the predetermined value in step S407, step S401 → step S402 → step S405 → step S406. The flow of going to step S407 → return is repeated. When the timer value exceeds the predetermined value in step S407, the flow from step S407 to step S404 → return is repeated, and in step S404, the torque down command is issued from the point in time when the timer value exceeds the predetermined value. Is output to the engine control unit 7 until the time of ending.

  That is, the present inventor, for the technical problem of aiming to stabilize the shift quality by the timer torque down control, when using the shift pressure learning correction control together, the shift pressure learning correction control works effectively in the learning correction fluctuation range, We paid attention to the fact that timer torque down control works effectively in the learning correction stable region. In accordance with this point of interest, in the learning correction fluctuation range, the timer torque down control that may deteriorate the speed change quality is prohibited, and when entering the learning correction stable range where the function of the speed change pressure learning correction control becomes low, A configuration that starts torque-down control is adopted. Then, in the learning correction fluctuation range, gear ratio torque down control that does not deteriorate the shift quality is executed as the torque reduction control at the time of shifting, and when entering the learning correction stable range, the timer torque is changed from the gear ratio torque down control. Added to down control.

  As described above, in the automatic transmission control apparatus according to the first embodiment, in the torque down switching control shown in FIG. 4, in step S402, the absolute difference value | Tt−Tr | between the target time Tt and the timer time Tr | Timer torque down control for determining the start timing by timer management is prohibited until it is determined that the learning correction stable range is less than the predetermined value, and the gear ratio torque down control is executed instead of the timer torque down control as described above. The

  Therefore, in the learning correction fluctuation range where the shift pressure learning correction has not converged, the timer torque down control is executed, and the start-up shock or driving force due to the deviation of the start timing of the inertia phase from the start timing of the torque down is caused. The occurrence of a pulling shock is prevented.

  Then, in the torque down switching control shown in FIG. 4, when it is determined in step S402 that the difference absolute value | Tt−Tr | between the target time Tt and the timer time Tr is less than a predetermined value, the timer is corrected. Timer torque down control for determining the start timing by management is executed.

Therefore, in the learning correction stable region where the shift pressure learning correction has converged, as shown in FIG. 9, the inertia phase start time Ti is stabilized, and thus coincides with the start time Td of timer torque down control by timer management. Sex is secured. For this reason, the excessive input torque to the transmission can be effectively suppressed in the inertia phase, so that the fluctuation range of the output shaft torque can be suppressed small as shown in the characteristics of the output shaft torque (T _OUT ) in FIG. Good shifting quality can be maintained. In addition, as the excess input torque to the transmission is effectively suppressed in the inertia phase, the gear ratio changes with a large gradient as shown in the characteristics of the gear ratio (Gr) in FIG. The speed is changed quickly in a short time, the heat load of the friction element is reduced, and the durability reliability of the friction element is ensured.

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

  (1) In the automatic transmission control device that achieves multiple shift stages by switching the engagement state of the friction elements in order to transmit the torque from the drive source (engine 1) to the drive wheels, the shift progresses during the current shift. A shift pressure learning correction control means (FIG. 3) for measuring the physical quantity representing the situation and correcting the engagement command pressure of the friction element at the next shift based on the deviation state between the actual physical quantity and the target physical quantity; Shifting torque that starts outputting a command to temporarily reduce the torque of the drive source (engine 1) at the expected start timing of the inertia phase preset by time management during the shift transition period from the start to the shift end Determine the convergence of the down pressure control means (step S405 → step S406 → step S407 to step S404) and the shift pressure learning correction control means. (Step S402), the torque-down control by the shift-torque-down control means is prohibited until it is determined that the shift pressure learning correction has converged, and when it is determined that the shift pressure learning correction has converged, the shift torque Torque down switching control means (FIG. 4) for executing torque down control by the down control means. For this reason, it is necessary to stabilize the transmission quality by preventing the occurrence of shift shock by torque down control in the learning correction fluctuation range and ensuring the consistency between the start timing of torque down control and the start timing of the inertia phase in the learning correction stability range. Can respond.

  (2) The shift pressure learning correction control means measures the time required from the time when the shift start command is output to the start of the inertia phase, and shifts based on the time difference between the timer measurement time from the shift start and the target time. 3 is a timer learning correction control means (FIG. 3) that determines and stores a correction amount of the engagement command pressure for the friction element involved in the shift element, and the shift torque down control means is configured to output the inertia phase from the output time of the shift start command. Timer time-down control for starting a command to temporarily reduce the torque of the drive source (engine 1) when a predetermined time has elapsed from the reference time, and a reference time is set Means (flow from step S405 → step S406 → step S407 to step S404). For this reason, the shift pressure learning correction control can be performed with high accuracy, and the same time management control is used for the learning correction control and the torque down control, thereby matching the start timing of the torque down control and the start timing of the inertia phase. Can be increased.

  (3) In addition to the timer torque down control means, as the shift torque down control means, a command to temporarily reduce the torque of the drive source (engine 1) when a gear ratio change indicating shift progress is confirmed during the shift. Gear ratio torque down control means (a flow proceeding from step S403 to step S404) is provided, and the torque down switching control means (FIG. 4) is a shift pressure by the timer learning correction control means (FIG. 3). The convergence of the learning correction is determined (step S402), and the gear ratio torque down control by the gear ratio torque down control means is executed until the shift pressure learning correction is determined to have converged. When it is determined that the motor has converged, the timer torque down control means (step S405 → step S406 → step S407) is used instead of the gear ratio torque down control. Timer torque down control according to the flow from step S404 to step S404. For this reason, the shift shock can be suppressed to be small by the gear ratio torque down control in the learning correction fluctuation range in which the timer torque down control is prohibited.

  (4) The torque down switching control means (FIG. 4) acquires the actual physical quantity and the target physical quantity from the shift pressure learning correction control means, and when the absolute value of the difference value between the actual physical quantity and the target physical quantity becomes less than a predetermined value, A learning correction convergence determination unit (step S402) that determines that the shift pressure learning correction has converged is provided. For this reason, the convergence of the shift pressure learning correction can be accurately determined based on the difference value between the actual physical quantity and the target physical quantity that determines the learning correction value, and at the time of disturbance input in which the start timing of the inertia phase is predicted to be unstable. In addition, since the actual physical quantity deviates from the target physical quantity, it can be determined that the shift pressure learning correction has not converged.

  As mentioned above, although the control apparatus of the automatic transmission of this invention has been demonstrated based on Example 1, it is not restricted to this Example 1 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 the learning correction amount is obtained by timer learning of the piston stroke time in which the timer time Tr measured in the shift transition period is matched with the target time Tt is shown. However, the learning correction amount may be obtained by gear ratio change rate learning in which the gear ratio change rate in the inertia phase matches the target change rate. Furthermore, the learning correction amount may be obtained by learning using both timer learning and gear ratio change rate learning.

In the timer learning correction control according to the first embodiment, the obtained learning correction amount ΔP is stored in a storage area that is subdivided according to a learning operation state such as a shift type and a throttle opening, and a shift corresponding to this storage area next time is stored. An example is shown in which the engagement command pressure is corrected using the learning correction amount ΔP stored only when the operation is performed. However, the engagement command pressure at the next shift may be corrected based on the learning correction amount ΔP even in a shift state different from when the learning correction amount ΔP is obtained. In this case, the correction amount of the engagement command pressure is calculated by, for example, multiplying the learning correction amount ΔP by a coefficient set based on the operation state at the time of the current shift such as the throttle opening.
When the timer learning correction control as described above is performed, the learning convergence determination correction unit learns based on the learning correction amount ΔP that is the same type as the current shift type and that corresponds to the shift operation state. The convergence determination of learning is performed based on the learning correction amount at the previous learning without performing the convergence determination.

  In the first embodiment, an example in which the timer torque down control unit that manages the required time from the time when the hydraulic switch is turned on to the time when the inertia phase is started by using the timer value is shown as the shift torque down control unit. However, it is also possible to use timer torque down control means for managing the required time from the time point of the shift start command to the time point when the inertia phase is started by using the timer value.

  In the first embodiment, as the gear ratio torque down control means, the gear ratio change rate is monitored, and when the gear ratio change rate exceeds a predetermined value, the torque down control is started. However, the gear ratio may be monitored, and the torque down control may be started when the gear ratio changes by a predetermined amount from the gear ratio before shifting to the gear ratio after shifting.

  In the first embodiment, as the learning correction convergence determination unit of the torque down switching control means, the target time Tt is acquired from the shift pressure learning correction control side, and the timer time Tr is the absolute value of the difference value of the target time Tt | An example is shown in which it is determined that the shift pressure learning correction has converged when Tr−Tt | is less than a predetermined value. However, a learning correction value may be acquired from the shift pressure learning correction control side, and when the learning correction value becomes less than a predetermined value, it may be determined that the shift pressure learning correction has converged. The learning correction experience frequency information may be acquired from the correction control side, and it may be determined that the shift pressure learning correction has converged if the learning correction experience frequency is equal to or greater than the set number.

  In the first embodiment, as an example of the engine torque reduction control, the electric throttle valve of the engine 1 is controlled in the closing direction. However, it is also possible to use a control for reducing the fuel injection amount without changing the throttle opening, a fuel cut control for changing the number of cylinders for fuel injection, or a retard control for retarding the ignition timing. Furthermore, when a motor is used as the drive source, control for reducing the motor drive current value may be used.

  In Example 1, the example of the control apparatus of the automatic transmission applied to the engine vehicle was shown. However, the present invention can also be applied to a hybrid vehicle in which an engine and a motor are mounted as a drive source, an electric vehicle in which a motor is mounted as a drive source, and the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall view showing a general control system for an engine and an automatic transmission in an engine vehicle to which an automatic transmission control device according to a first embodiment is applied. FIG. 3 is an upshift pattern diagram illustrating an example of an upshift line set in an automatic transmission control unit of the automatic transmission control device according to the first embodiment. 7 is a flowchart showing a flow of timer learning correction control processing executed by the automatic transmission controller 8 according to the first embodiment. 4 is a flowchart showing a flow of torque down switching control processing executed by the automatic transmission controller 8 according to the first embodiment. It is a time chart showing the characteristics of the gear ratio, engine torque, and output shaft torque when the start timing of the inertia phase is earlier than the start timing of the timer torque down control because the engagement hydraulic pressure is higher than the optimum pressure at the time of upshift. . 6 is a time chart showing the characteristics of gear ratio, engine torque, and output shaft torque when the start timing of the inertia phase becomes later than the start timing of timer torque down control due to the engagement hydraulic pressure being lower than the optimum pressure during upshifting. In order to explain the timer learning correction control in the control apparatus for the automatic transmission according to the first embodiment, the output torque, the gear ratio change rate, the gear ratio, and the upshift engagement hydraulic command in the upshift transition period (an example of the shift transition period) are described. It is a time chart which shows a characteristic. Gear ratio (Gr), engine torque (TRD), release pressure (P _OUT ), engagement pressure (P) in gear ratio torque down control executed in the learning correction fluctuation range in the automatic transmission control device of the first embodiment. It is a time chart showing each characteristic of _IN ) and output shaft torque (T _OUT ). Gear ratio (Gr), engine torque (TRD), release pressure (P _OUT ), engagement pressure (P _IN ) in timer torque down control executed in the learning correction stable region in the automatic transmission control device of the first embodiment. ) _-A time chart showing each characteristic of the output shaft torque (T _OUT ).

Explanation of symbols

1 Engine (drive source)
2 Torque converter 3 Automatic transmission 31 Friction element (friction element) during upshift
32 Releasing friction element during upshifting (friction element)
4 Transmission output shaft 5 Engine torque control actuator 6 Control valve unit 7 Engine control unit 8 Automatic transmission control unit 9 Intercommunication line 10 Throttle opening sensor 11 Vehicle speed sensor 12 Turbine speed sensor 13 Accelerator operation amount sensor 14 Hydraulic switch 15 Other sensors and switches

Claims (4)

In a control device for an automatic transmission that achieves a plurality of shift stages by switching the engagement state of a friction element to transmit torque from a drive source to drive wheels,
A shift pressure learning correction control means for measuring a physical quantity representing a shift progress state at the time of the current shift, and correcting the engagement command pressure of the friction element at the next shift based on a deviation state between the actual physical quantity and the target physical quantity;
Shifting torque that starts outputting a command to temporarily reduce the torque of the drive source at the expected start timing of the inertia phase preset by time management during the shift transition period from the start of shifting to the end of shifting at the time of shifting Down control means;
The convergence of the shift pressure learning correction by the shift pressure learning correction control means is determined, and the torque down control by the shift torque reduction control means is prohibited until it is determined that the shift pressure learning correction has converged, and the shift pressure learning correction is performed. Torque down switching control means for executing torque down control by the shift torque down control means when it is determined that
A control device for an automatic transmission, comprising: The control device for an automatic transmission according to claim 1,
The shift pressure learning correction control means measures the time required from the output start time of the shift start command to the start time of the inertia phase, and is involved in the shift based on the time difference between the timer measurement time from the shift start and the target time. Timer learning correction control means for determining and storing a correction amount of the engagement command pressure to the friction element,
The shift torque down control means sets a reference time from the output time point of the shift start command to the start point of the inertia phase, and when a predetermined time has elapsed from the reference time, the torque of the drive source A control device for an automatic transmission, characterized in that it is a timer torque down control means for starting output of a command for temporarily reducing the torque. The control apparatus for an automatic transmission according to claim 2,
As the shift torque down control means, in addition to the timer torque down control means, a gear ratio for starting output of a command to temporarily reduce the torque of the drive source when a gear ratio change indicating shift progress is confirmed during a shift. Torque down control means is provided,
The torque down switching control means determines the convergence of the shift pressure learning correction by the timer learning correction control means, and until it is determined that the shift pressure learning correction has converged, the gear ratio torque down control means When the specific torque down control is executed and it is determined that the shift pressure learning correction has converged, the timer torque down control by the timer torque down control means is executed instead of the gear ratio torque down control. Control device for automatic transmission. The control device for an automatic transmission according to any one of claims 1 to 3,
The torque down switching control means acquires the actual physical quantity and the target physical quantity from the shift pressure learning correction control means, and when the absolute value of the difference value between the actual physical quantity and the target physical quantity becomes less than a predetermined value, the shift pressure learning correction converges. A control device for an automatic transmission, comprising: a learning correction convergence determination unit that determines that the transmission is correct.

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