JP2011163169A - Control device of automatic transmission - Google Patents

Abstract

A control device for an automatic transmission in which a pull-in torque generated by generation of an on-side (speed-destination speed stage) clutch torque in a torque phase of a shift is not dependent on a response of a clutch hydraulic pressure.
Engine torques Te1 and Te2 before and after a shift are estimated, and based on the estimated engine torques Te1 and Te2 before and after the shift, the engine torque Te in the torque phase is equivalent to an output torque after the shift (Te2 × i2). / I1, i1: the gear ratio of the speed stage before the shift, and i2: the gear ratio of the speed stage after the shift) are once suddenly decreased (ΔTRQ = ΔTRQst), and then gradually recovered to the inertia phase (ΔTRQ = ΔTRQst + ΔTRQon) The engine torque fluctuation amount ΔTRQ is calculated at the same time, and the engine operation is controlled via the ignition timing so that the engine torque Te fluctuates according to the calculated fluctuation amount ΔTRQ.
[Selection] Figure 3

Description

  The present invention relates to a control device for an automatic transmission, and more specifically, to a device that improves a shift feeling.

  In Patent Document 1 below, while increasing the engine torque in the torque phase of the shift, reducing the shock in the inertia phase, the shift shock is suppressed, and the intake air amount is increased prior to the change of the engine torque. Techniques to improve are proposed.

JP 2007-231870 A

  By the way, in the torque phase of the shift, the pull-in torque is mainly generated by the generation of the clutch torque (transmission torque of the friction engagement element (hydraulic clutch)) on the ON side (speed stage of the shift destination). Since it depends on the responsiveness of the clutch hydraulic pressure, it is difficult to always obtain a desired shift feeling in the torque phase, and the shift feeling is different for each hydraulic clutch.

  In this regard, the technique described in Patent Document 1 only discloses a technique for increasing the engine torque in the torque phase of the shift and increasing the intake air amount prior to the change of the engine torque.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and to prevent the pull-in torque generated by the generation of the on-side (shift destination speed stage) clutch torque in the torque phase of the shift from depending on the response of the clutch hydraulic pressure. It is to provide a control device.

  In order to solve the above-described problem, according to claim 1, in the control device for an automatic transmission that shifts the output of the engine mounted on the vehicle via the friction engagement element, the engine torque before and after the shift is changed. Based on the engine torque estimation means for estimating the engine torque before and after the estimated shift, the engine torque suddenly decreases by an amount equivalent to the output torque after the shift of the transmission once in the torque phase, and then until the inertia phase. Engine torque fluctuation amount calculating means for calculating the fluctuation amount of the engine torque so as to gradually recover, and engine control means for controlling the operation of the engine so that the engine torque fluctuates according to the calculated fluctuation amount. It was configured to provide.

  In the automatic transmission control apparatus according to claim 2, the engine control means is configured to control the operation of the engine by adjusting an ignition timing.

  In the control device for an automatic transmission according to claim 1, the torque of the engine before and after the shift is estimated, and the engine torque in the torque phase corresponds to the output torque after the shift of the transmission based on the estimated engine torque. The amount of change in the engine torque is gradually reduced until the inertia phase, more specifically, the speed stage of the shift destination, that is, gradually recovering in synchronization with the generation of the on-side clutch torque. Since the engine operation is controlled so that the engine torque fluctuates according to the calculated fluctuation amount, it is possible to cancel the pull-in torque due to the generation of the on-side clutch torque. Can be made independent of the responsiveness of the hydraulic pressure, so that a desired speed change feeling can be obtained in the torque phase. Rutotomoni, shift feeling nor differ for each frictional engagement element (hydraulic clutch).

  Furthermore, since the torque input to the friction engagement element is reduced, the durability of the friction engagement element can be improved, and the response of shifting can be improved even at an extremely low oil temperature.

  The automatic transmission control device according to claim 2 is configured to control the operation of the engine by adjusting the ignition timing. Since the intake air amount is not changed, the response of the engine torque control can be further improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an entire automatic transmission control apparatus according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the control apparatus of the automatic transmission shown in FIG. 2 is a time chart for explaining the processing of the flow chart. FIG. 3 is a sub-routine flowchart showing an estimation process of the off-side and on-side clutch torques of the flowchart of FIG. 2.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments for implementing a control device for an automatic transmission according to the invention will be described with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing an overall control apparatus for an automatic transmission according to an embodiment of the present invention.

  In the following description, the symbol T indicates an automatic transmission (hereinafter referred to as “transmission”). The transmission T is mounted on a vehicle (not shown) and is a parallel shaft stepped type having speed stages of 5 forward speeds and 1 reverse speed.

  The transmission T includes a main shaft (input shaft) MS connected to an output shaft 10 connected to a crankshaft of an engine (internal combustion engine) E via a torque converter 12 having a lockup mechanism L, and the main shaft MS. And a counter shaft (output shaft) CS connected via a plurality of gear trains. The engine E includes a plurality of cylinders and a spark ignition engine using gasoline as fuel.

  A main first speed gear 14, a main second speed gear 16, a main third speed gear 18, a main fourth speed gear 20, a main fifth speed gear 22, and a main reverse gear 24 are supported on the main shaft MS.

  The counter shaft CS has a counter first speed gear 28 meshing with the main first speed gear 14, a counter second speed gear 30 meshing with the main second speed gear 16, a counter third speed gear 32 meshing with the main third speed gear 18, The counter 4th gear 34 meshed with the main 4th gear 20, the counter 5th gear 36 meshed with the main 5th gear 22, and the counter reverse gear 42 connected to the main reverse gear 24 via the reverse idle gear 40 are supported. Is done.

  In the above description, when the main first-speed gear 14 that is rotatably supported on the main shaft MS is coupled to the main shaft MS by a first-speed hydraulic clutch (friction engagement element; the same applies hereinafter) C1, the first speed (gear, speed stage) is coupled. ) Established.

  When the main second-speed gear 16 that is rotatably supported on the main shaft MS is coupled to the main shaft MS by the second-speed hydraulic clutch C2, the second speed (gear, speed stage) is established. When the counter third-speed gear 32 that is rotatably supported on the countershaft CS is coupled to the countershaft CS by the third-speed hydraulic clutch C3, the third speed (gear, speed stage) is established.

  With the counter fourth speed gear 34 supported rotatably on the counter shaft CS coupled to the counter shaft CS by the selector gear SG, the main fourth speed gear 20 supported relatively rotatably on the main shaft MS is changed to the fourth speed-reverse. When the hydraulic clutch C4R is coupled to the main shaft MS, the fourth speed (gear, speed stage) is established.

  Further, when the counter fifth-speed gear 36 that is rotatably supported on the countershaft CS is coupled to the countershaft CS by the fifth-speed hydraulic clutch C5, the fifth speed (gear, speed stage) is established.

  Further, with the counter reverse gear 42 supported relative to the countershaft CS rotatably coupled to the countershaft CS by the selector gear SG, the main reverse gear 24 supported relative to the main shaft MS relative to the countershaft CS is connected to the 4-speed-reverse. When the main hydraulic clutch C4R is coupled to the main shaft MS, a reverse speed stage is established.

  The rotation of the counter shaft CS is transmitted to the differential D through a final drive gear 46 and a final driven gear 48, and then a vehicle (not shown) on which the engine E and the transmission T are mounted via the left and right drive shafts 50, 50. Are transmitted to the drive wheels W, W.

  A shift lever 54 is provided near the floor of the vehicle driver's seat (not shown), and one of eight ranges, P, R, N, D5, D4, D3, 2, 1 is selected by the driver's operation. The

  A throttle valve (not shown) disposed in the intake passage (not shown) of the engine E is connected to a DBW (Drive By Wire) mechanism 55. That is, the throttle valve is mechanically disconnected from an accelerator pedal (not shown) and driven by an actuator (not shown) such as an electric motor.

  A throttle opening sensor 56 is provided in the vicinity of the actuator of the DBW mechanism 55 and outputs a signal indicating the throttle opening THHF through the rotation amount of the actuator. A vehicle speed sensor 58 is provided in the vicinity of the final driven gear 48 and outputs a signal indicating the vehicle speed V every time the final driven gear 48 makes one rotation.

  Further, a crank angle sensor 60 is provided in the vicinity of the camshaft (not shown), and a CYL signal is subdivided at a predetermined crank angle of a specific cylinder, a TDC signal is subdivided at a predetermined crank angle of each cylinder, and a crank obtained by subdividing the predetermined crank angle. A CRK signal is output for each angle (for example, 15 degrees). Further, an absolute pressure sensor 62 is provided downstream of the throttle valve arrangement position of the intake passage of the engine E, and outputs a signal indicating the intake pipe absolute pressure (engine load) PBA.

  A first rotation speed sensor 64 is provided in the vicinity of the main shaft MS and outputs a signal indicating the rotation speed (input rotation speed of the transmission T) NM of the main shaft MS, and in the vicinity of the counter shaft CS. A second rotational speed sensor 66 is provided, and outputs a signal indicating the rotational speed of the countershaft CS (output rotational speed of the transmission T) NC.

  Further, a shift lever position sensor 68 is provided in the vicinity of the shift lever 54 mounted in the vicinity of the vehicle driver's seat, and outputs a signal indicating the position selected by the driver among the eight positions (ranges) described above. To do.

  Further, a temperature sensor 70 is provided in the vicinity of the reservoir of the hydraulic circuit O of the transmission T to output a signal proportional to the oil temperature (the temperature of the hydraulic oil Automatic Transmission Fluid) TATF, and the oil path connected to each clutch. Are each provided with a hydraulic switch 72, which outputs an ON signal when the hydraulic pressure supplied to each clutch reaches a predetermined value.

  A brake switch 74 is provided in the vicinity of a brake pedal (not shown) in the vehicle driver's seat, and outputs an ON signal in response to the driver's brake pedal operation, and in the vicinity of an accelerator pedal (not shown). An accelerator opening sensor 76 is provided to generate an output corresponding to the driver's accelerator opening (accelerator pedal depression amount) AP.

  Outputs of these sensors 56 and the like are sent to an ECU (electronic control unit) 80.

  The ECU 80 includes a microcomputer including a CPU 82, ROM 84, RAM 86, an input circuit 88, and an output circuit 90. The microcomputer includes an A / D converter 92.

  The output of the sensor 56 and the like is input into the ECU 80 via the input circuit 88, the analog output is converted into a digital value via the A / D converter 92, and the digital output is processed by a waveform shaping circuit or the like. It is processed through a circuit (not shown) and stored in the RAM 86.

  The time interval between the output of the vehicle speed sensor 58 and the output of the CRK signal of the crank angle sensor 60 is measured by a counter (not shown), and the vehicle speed V and the engine speed Ne are detected. The outputs of the first rotational speed sensor 64 and the second rotational speed sensor 66 are also counted, and the input shaft rotational speed NM and the output shaft rotational speed NC of the transmission are detected.

  In the ECU 80, the CPU 82 determines a destination stage or a target stage (gear ratio), and excites / de-energizes shift solenoids SL1 to SL5 arranged in the hydraulic circuit O via an output circuit 90 and a voltage supply circuit (not shown). The clutch oil passage switching control is performed, and the linear solenoids SL6 to SL8 are excited and de-energized to control the hydraulic pressure supplied to the hydraulic clutch Cn and the lockup mechanism L of the torque converter 12 related to the shift.

  Further, the CPU 82 determines the fuel injection amount and ignition timing of the engine E, supplies the determined injection amount of fuel via an injector (not shown), and is determined via an ignition device (not shown). The fuel / intake mixture is ignited according to the ignition timing.

  Next, the operation of the automatic transmission control device according to the present invention will be described.

  FIG. 2 is a flow chart showing the processing, and FIG. 3 is a time chart for explaining the processing of the flow chart of FIG. The illustrated program is executed by the CPU 82 every predetermined time.

  In the following description, in S10, the off-side clutch torque (transmission torque of the hydraulic clutch Cn at the speed stage before the shift) Toff and the on-side clutch torque (transmission torque of the hydraulic clutch Cn at the speed stage of the shift destination) Ton are estimated. .

  FIG. 4 is a sub-routine flowchart showing the processing.

  Explained below, in S100, it is determined whether or not there is an UP (up) shift, that is, an upshift such as 1st to 2nd, 2nd to 3rd. For example, when downshifting, upshifting has been completed, or when the gearshift state is not in the first place, the process proceeds to S102 and S104, and both the off-side and on-side clutch torques Toff and Ton are set to zero. Set to.

  On the other hand, when the result in S100 is affirmative, the program proceeds to S106, in which the engine torque Te1 before shifting is estimated. This is calculated by searching an appropriate map from the engine speed Ne at that time and the intake pipe absolute pressure PBA.

  Next, in S108, the engine torque Te2 after the shift is estimated. The engine torque Te2 after the shift is also calculated by searching an appropriate map from the engine speed expected after the shift and the intake pipe absolute pressure PBA.

  Next, in S110, it is determined whether or not the on-side clutch torque Ton has exceeded zero. If it is before time t1 in FIG. 3, the determination is denied and the routine proceeds to S112, where the value obtained by multiplying the engine torque Te1 before the shift by the coefficient k is set as the off-side clutch torque Toff. K is set to a value of 1.0 or more so that the off-side hydraulic clutch Cn does not slip.

  On the other hand, if it is after time t1 in FIG. 3, the determination in S110 is affirmed and the process proceeds to S114, in which it is determined whether or not it is in the I phase (inertia phase).

  If it is before time t2 in FIG. 3, the determination in S114 is negative and the process proceeds to S116, where the off-side clutch torque Toff is subtracted and corrected, and the process proceeds to S118 where the on-side clutch torque Ton is added and corrected.

  On the other hand, if it is after time t2 in FIG. 3, the determination in S114 is affirmed and the routine proceeds to S120, where the off-side clutch torque Toff is set to zero. Next, in S122, the on-side clutch torque Ton is set to the engine torque Te2 after the shift.

  Returning to the description of the flow chart of FIG. 2, the process then proceeds to S12, where it is determined again whether or not it is an UP (up) shift, and when the result is negative, the process proceeds to S14 and the value ΔTRQ is set to zero.

  Before continuing the description of the flow chart of FIG. 2, the processing of the flow chart of FIG. 2 will be described with reference to the time chart of FIG.

  In this embodiment, the engine torque before and after the shift (the output torque of the engine E) Te, more specifically, the engine torque Te1 before the shift and the engine torque Te2 after the shift are estimated, and the estimated engine torque Te1, Based on Te2, the engine torque Te is suddenly decreased in the torque phase (ΔTRQ = ΔTRQst), and then the engine torque fluctuation amount ΔTRQ is calculated so that it gradually increases until the inertia phase (ΔTRQ = ΔTRQst + ΔTRQon). The operation of the engine E is controlled so as to fluctuate according to the fluctuation amount ΔTRQ, more specifically, by controlling the ignition timing. TRQon is an estimated torque value generated by the ON-side hydraulic clutch Cn.

  Returning to the description of the flow chart of FIG. 2, the process then proceeds to S16, where it is determined again whether or not the on-side clutch torque Ton exceeds zero. When the result is negative, the process proceeds to S14, while when the result is positive, the process proceeds to S18. It is determined whether or not it is the first time, that is, the first time after the execution of the flowchart of FIG. 2 is affirmed in S16.

  When the result in S18 is affirmative, the program proceeds to S20, and an engine torque sudden decrease (initial value) ΔTRQst (negative value) is calculated according to the following equation.

ΔTRQst = Te1-Te2 × i2 / i1
In the above, i1: gear ratio of the speed stage before the shift, i2: gear ratio of the speed stage after the shift. In the above equation, the second term on the right side corresponds to the output torque Tout after the shift estimated from the engine torque Te2.

  Accordingly, the sudden decrease amount ΔTRQst of the engine torque means a value that rapidly decreases the engine torque Te1 before the shift by an amount corresponding to the output torque Tout after the shift, as shown in FIG.

  Next, in S22, the calculated sudden decrease amount ΔTRQst is set as a variation amount ΔTRQ of the engine torque Te. As is apparent from FIG. 3, the processing from S20 to S22 is executed only once at time t1.

  Next, in S24, ignition timing control is executed. That is, the engine torque variation amount ΔTRQ is calculated so that the engine torque Te suddenly decreases once in the torque phase (ΔTRQ = ΔTRQst), and ignition is performed so that the engine torque Te varies according to the variation amount ΔTRQ, specifically, decreases. The timing is retarded.

On the other hand, when the result in S18 is negative, the program proceeds to S26, in which it is determined whether or not the vehicle is in the I phase. When the result in S26 is negative, the program proceeds to S28, and the engine torque increase amount ΔTRQon (positive value) is calculated according to the following equation.
ΔTRQon = Ton × (i1-i2) / i1

  Next, the process proceeds to S30, and the value obtained by adding the calculated increase amount ΔTRQon to the sudden decrease amount ΔTRQst (negative value) and correcting the decrease is used as the engine torque Te variation amount ΔTRQ. As shown in FIG. 3, the processing from S20 to S22 is executed a plurality of times from time t1 to t2.

  Next, in S24, ignition timing control is executed. That is, after the engine torque Te is suddenly decreased in the torque phase (ΔTRQ = ΔTRQst), the engine torque fluctuation amount ΔTRQ is calculated so that it gradually recovers (increases) until the inertia phase (ΔTRQ = ΔTRQst + ΔTRQon), and the engine torque is calculated. The ignition timing is controlled to advance so that Te varies according to the variation ΔTRQ, specifically, increases.

On the other hand, when the result in S26 is affirmative, the program proceeds to S32, and an engine torque reduction amount ΔTRQi (negative value) is calculated according to the following equation.
ΔTRQi = I × Δω / t

  In the above, I: inertia of engine E, Δω: rotation amount of engine E, t: time. That is, the reduction amount of the engine torque is calculated so as to absorb the inertia of the engine E at time t.

  Next, the routine proceeds to S34, where the calculated decrease amount ΔTRQi is set as the variation amount ΔTRQ of the engine torque Te, and the processing proceeds to S24, where the ignition timing is retarded so that the engine torque Te varies according to the variation amount ΔTRQ, specifically, decreases. .

  As described above, in this embodiment, in the control device (ECU 80) of the automatic transmission (transmission) T that changes the output of the engine E mounted on the vehicle via the friction engagement element (hydraulic clutch Cn). Based on the engine torque estimation means (S106, S108) for estimating the engine torques Te1 and Te2 before and after the shift and the estimated engine torque before and after the shift, the engine torque Te is once suddenly decreased in the torque phase. (ΔTRQ = ΔTRQst), engine torque fluctuation amount calculating means (S18 to S22, S36 to S34) for calculating the engine torque fluctuation amount ΔTRQ so as to gradually recover to the inertia phase (ΔTRQ = ΔTRQst + ΔTRQon), and the engine Torque Te follows the calculated fluctuation amount ΔTRQ The engine control means (S24) for controlling the operation of the engine so as to fluctuate, that is, after the engine torque Te suddenly decreases by an amount corresponding to the output torque Tout after the shift in the torque phase, until the inertia phase Since the engine torque Te is varied so that it gradually recovers (increases) gradually, more specifically in synchronization with the generation of the clutch torque on the ON side, more specifically on the speed side of the shift destination, It is possible to cancel the pull-in torque generated by the generation of the transmission torque (clutch torque) Ton of the hydraulic clutch (friction engagement element), and as a result, the pull-in torque, in other words, the output torque Tout of the transmission T is the response of the hydraulic pressure. In the torque phase so that the desired speed change feeling can be achieved. It is possible to obtain the speed change feeling for each hydraulic clutch (friction engagement element) Cn.

  That is, as shown by the output torque Tout in FIG. 3, in this embodiment, compared with the case where the output torque Tout indicates “conventional” in the torque phase, the responsiveness of the hydraulic pressure of the hydraulic clutch Cn is constant. It can be made not to depend on. Also in the inertia phase, the output torque Tout can be set to a constant value by performing the engine torque reduction control by ΔTRQi.

  Further, since the torque input to the hydraulic clutch Cn is reduced, the durability of the hydraulic clutch Cn can be improved, and the responsiveness of the shift can be improved even at an extremely low oil temperature.

  Further, since the engine control means is configured to control the E operation of the engine by adjusting the ignition timing (S28), in addition to the effects described above, the intake air amount is previously set as in the technique described in Patent Document 1. Therefore, the response of the engine torque control can be further improved.

  Although the present invention has been described by taking a parallel shaft type automatic transmission as an example, the present invention is also applicable to a planetary type automatic transmission and the like, and further to DCT (Dual Clutch Transmission).

  T automatic transmission (transmission), E engine (internal combustion engine), O hydraulic circuit, 12 torque converter, L lockup mechanism, 14, 16, 18, 20, 22, 24, 28, 30, 32, 34, 36, 42 gear, Cn hydraulic clutch (friction engagement element), 55 DBW mechanism, 58 vehicle speed sensor, 60 crank angle sensor, 62 absolute pressure sensor, 64, 66 rotation speed sensor, 76 accelerator opening sensor, 80 electronic control unit (ECU) )

Claims (2)

  In a control device for an automatic transmission that changes the output of an engine mounted on a vehicle via a friction engagement element, engine torque estimation means for estimating the engine torque before and after the shift, and before and after the estimated shift Based on the engine torque, the engine torque that calculates the fluctuation amount of the engine torque so that it gradually recovers to the inertia phase after the engine torque is suddenly reduced by an amount corresponding to the output torque after the shift of the transmission. A control device for an automatic transmission, comprising: a fluctuation amount calculating means; and an engine control means for controlling the operation of the engine so that the engine torque fluctuates according to the calculated fluctuation amount.   2. The automatic transmission control apparatus according to claim 1, wherein the engine control means controls the operation of the engine by adjusting an ignition timing.

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