JP2010185523A - Gear shift control device of automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gear shift control device of an automatic transmission which can enhance learning accuracy of an engagement side oil pressure and improve drivability in gear shift. <P>SOLUTION: The gear shift control device measures an actual gear shift time to be used in actual gear shift (step S21), calculates an amount of correction based on the actual gear shift time and target gear shift time (step S22), and corrects an engagement start learning value by the amount of correction (step S23). In the next gear shift, the engagement start time is subjected to learning correction by the above-determined engagement start learning value (step S17). This allows the gear shift time to be optimized by subjecting the engagement start time for increasing the engagement side oil pressure to the engagement start time subjected to learning correction. Thus, the learning accuracy of the gear shift time can be enhanced by simple control and the drivability in gear shift can be improved. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a shift control device for an automatic transmission, and more particularly to a shift control device for an automatic transmission that executes torque-up of a power source during a downshift.

  2. Description of the Related Art Conventionally, in a shift control device for an automatic transmission having a plurality of friction engagement devices, when performing shift control by releasing and engaging the friction engagement device, the release side that is supplied to the release friction engagement device The hydraulic pressure and the engagement-side hydraulic pressure supplied to the engagement-side friction engagement device are optimized to improve the drivability of the vehicle at the time of shifting.

  In addition, as a shift control device of this type of automatic transmission, one that establishes a gear stage only by engagement control of a friction engagement device is known (for example, see Patent Document 1).

  In the conventional shift control device described in Patent Document 1, when the predetermined gear stage is established from the state where the input rotational speed of the automatic transmission is lower than the synchronous rotational speed of the predetermined gear stage, By controlling the engagement force of the friction engagement device so that the rotation speed approaches the synchronous rotation speed after the rotation speed exceeds the synchronous rotation speed of the predetermined gear stage, only the engagement control of the friction engagement device is performed. Is established smoothly.

  Also, as a shift control device for this type of automatic transmission, in the shift control at the time of downshift, the torque of the power source is increased to shorten the time required for the downshift and to reduce the output loss. What improves responsiveness is known (for example, refer patent document 2).

  In the conventional shift control device described in Patent Document 2, when a downshift instruction is input from the shift lever, the release side hydraulic pressure starts to be reduced, and a torque increase is instructed to the power source. By increasing the input shaft rotational speed of the automatic transmission connected to the output shaft of the power source through the input shaft, the input shaft rotational speed is brought close to the synchronous rotational speed at the end of the shift, and the shift time is shortened. Yes.

  Further, when executing torque increase, by stopping the generation of power by some of the cylinders constituting the internal combustion engine as a power source, the pumping loss in the internal combustion engine is reduced, thereby The increase in the output shaft rotation speed of the power source is accelerated, and the shift response is improved.

Japanese Patent Laid-Open No. 2001-065680 JP 2008-144738

  However, in the conventional transmission control device for an automatic transmission described in Patent Document 1, the gear stage is established only by the engagement control of the friction engagement device, but the same control value is used. Even if the combined control is performed, the actual rate of change of the rotational speed differs for each vehicle, and the shift time is not optimally controlled. Further, control such as rapid increase of the input rotation speed and smooth establishment of the gear stage has to be performed only by controlling the engagement hydraulic pressure of the friction engagement device. Therefore, both extreme control of rapid increase of engagement hydraulic pressure and minute change of hydraulic pressure must be performed in a short time. The more precise control, the more complicated the control and the actual fluctuation of hydraulic pressure can be. There was a risk of being unable to fill.

  Further, in the conventional transmission control device for an automatic transmission described in Patent Document 2, although the increase in the output rotational speed of the power source at the time of torque increase is accelerated, the difference between vehicles and the change over time It did not consider changes due to. For this reason, when the actual amount of increase in the rotational speed with respect to the torque increase request amount, the engagement ratio with respect to the hydraulic pressure, and the like are different, the shift time is not optimized and the shift characteristics may vary. was there.

  Therefore, in any case, it does not correspond to the characteristics of each vehicle and the difference in shift time due to changes over time, and as a result, the shift characteristics vary and the drivability deteriorates, for example, the shift feeling is impaired. Has occurred.

  The present invention has been made to solve such problems, and provides a shift control device for an automatic transmission that can improve the learning accuracy of the shift time and improve the drivability at the time of shift with simple control. The purpose is to do.

  In order to achieve the above object, the shift control device for an automatic transmission according to the present invention is (1) connected to a power source via an input shaft, and a plurality of hydraulic friction engagement devices are selectively engaged. A predetermined disengagement side frictional engagement device among the plurality of hydraulic engagement devices is released from the automatic transmission provided with a transmission mechanism in which a plurality of gear stages having different gear ratios is established by the predetermined engagement. In an automatic transmission shift control device that engages a side frictional engagement device and executes a downshift shift control that increases the torque of the power source, an input rotation speed detection that detects the rotation speed of the input shaft of the transmission mechanism Means for detecting the rotation speed of the output shaft of the transmission mechanism, instruction detection means for detecting the downshift instruction, and detection of the downshift instruction by the instruction detection means as a trigger. Torque up control means for executing torque up to the source and controlling the torque amount in the torque up, and when the engagement start time corresponding to a preset target shift time has elapsed from the detection of the downshift instruction, The hydraulic control means for controlling the engagement side hydraulic pressure to be supplied to the engagement side frictional engagement device to satisfy the torque capacity, and the synchronization of the rotation speed of the input shaft and the rotation speed of the output shaft, Shift end determining means for determining the end of shift, actual shift time measuring means for measuring an actual shift time from detection of the downshift instruction to determination of shift end of the automatic transmission, the target shift time and the actual shift And a learning correction unit that calculates a correction amount of the engagement start time based on time and learns and corrects the engagement start time.

  With this configuration, the actual shift time required for the actual shift is measured, and the engagement start time is learned and corrected based on the actual shift time and the target shift time. Since the engagement timing suitable for the vehicle can be set, and the engagement start time for increasing the engagement-side hydraulic pressure can be set to the engagement start time corrected by learning, the shift time can be optimized. The learning accuracy of the shift time can be improved by simple control, and the drivability during the shift can be improved.

  A shift control device for an automatic transmission according to the present invention is the shift control device for an automatic transmission described in (1) above. (2) Vehicle speed detection means for detecting the speed of a vehicle equipped with the automatic transmission. And target time calculation means for calculating the target shift time according to the gear selected by the downshift instruction and the detected vehicle speed, and the learning correction means calculates the correction amount. Correction amount calculation means for performing correction, a learning value correction means for correcting the learning value for calculating the engagement start time from the target shift time based on the correction amount, and the engagement from the target shift time based on the corrected learning value. And an engagement time calculation means for calculating a start time.

  The vehicle speed detecting means may detect the vehicle speed based on the rotation speed of the output shaft of the automatic transmission detected by the output shaft rotation speed detection means instead of the output shaft rotation speed detection means. Also good. On the other hand, the output shaft rotational speed detection means substitutes the vehicle speed detection means, and detects the rotational speed of the output shaft of the automatic transmission based on the vehicle speed detected by the vehicle speed detection means. Also good.

  With this configuration, learning correction is performed at the engagement start time corresponding to the target shift time corresponding to the gear stage and vehicle speed at the time of shift, so learning according to the situation at the time of shift can be performed, and the learning accuracy of the shift time is improved. Can be increased.

  The automatic transmission shift control device according to the present invention is the automatic transmission shift control device according to the above (1) or (2), wherein (3) the learning correction means is configured so that the actual shift time is When the shift speed is shorter than the target shift time, learning correction is performed so that the engagement start time is delayed, and when the actual shift time is longer than the target shift time, learning correction is performed so that the engagement start time is advanced. It has the structure characterized by these.

  With this configuration, when the actual shift time is shorter than the target shift time, the learning start correction is performed so that the engagement start time is delayed, and when the actual shift time is longer, the engagement start time is controlled to an optimal value. Therefore, the engagement timing suitable for the actual vehicle can be obtained, and the learning accuracy of the shift time can be improved by simple control, and the drivability at the time of shift can be improved.

  The automatic transmission shift control device according to the present invention is the automatic transmission shift control device according to any one of (1) to (3), wherein (4) the learning correction means includes the target shift time and the Based on the actual shift time, a correction amount of the torque amount controlled by the torque-up control means is calculated, and the torque amount at the time of the torque increase is learned and corrected.

  With this configuration, the amount of torque at the time of torque increase is corrected by the actual shift time, so that the amount of change in the rotational speed of the input shaft can be changed, and the time itself that the rotational speed of the input shaft approaches the rotational speed of the output shaft For example, the range of control can be expanded, and the learning accuracy of the shift time can be increased.

  ADVANTAGE OF THE INVENTION According to this invention, the shift control apparatus of the automatic transmission which improves the learning precision of shift time by simple control and improves the drivability at the time of shift can be provided.

1 is a schematic configuration diagram illustrating a vehicle equipped with a shift control device for an automatic transmission according to an embodiment of the present invention. 1 is a skeleton diagram showing a configuration of an automatic transmission according to an embodiment of the present invention. It is an operation | movement table | surface of the automatic transmission in embodiment of this invention. It is a circuit diagram which shows schematic structure of the hydraulic control circuit in embodiment of this invention. It is a timing chart for demonstrating the control timing of transmission ECU in embodiment of this invention. It is a figure which shows the target shift time setting map in embodiment of this invention. It is a flowchart for demonstrating the shift control process in embodiment of this invention.

Hereinafter, a shift control apparatus for an automatic transmission according to an embodiment of the present invention will be described with reference to FIGS.
In the present embodiment, a case will be described in which the shift control device for an automatic transmission according to the present invention is applied to an FF (Front engine Front drive) vehicle.

  As shown in FIG. 1, the vehicle 1 controls the engine 2 as a power source, a torque converter 3, a transmission mechanism 4 having a plurality of hydraulic friction engagement devices, and the torque converter 3 and the transmission mechanism 4 by hydraulic pressure. A hydraulic control circuit 9 for controlling the engine 2, an engine ECU (Electronic Control Unit) 11 for controlling the engine 2, and a transmission ECU 12 for controlling the hydraulic control circuit 9.

  The engine 2 constitutes an internal combustion engine that burns a mixture of fuel and air injected from an injector (not shown) in a combustion chamber of a cylinder. The piston in the cylinder is pushed down by the combustion in the combustion chamber, and the crankshaft 41 (see FIG. 2) as the output shaft is rotated. An external combustion engine may be used instead of the internal combustion engine.

  The torque converter 3 increases the torque from the engine 2 to the speed change mechanism 4 to transmit the power of the engine 2 and, as will be described later, is a pump connected to the output shaft (crankshaft) 41 of the engine 2. An impeller (hereinafter simply referred to as an impeller) 43, a turbine runner (hereinafter simply referred to as a turbine) 44 coupled to an input shaft 48 of the speed change mechanism 4, and a stator 46 that is prevented from rotating in one direction by a one-way clutch 45. have. The impeller 43 and the turbine 44 transmit power via a fluid.

  Furthermore, the torque converter 3 is a lock-up clutch 47 (in order to increase power transmission efficiency from the engine 2 to the transmission mechanism 4 by mechanically connecting the impeller 43 and the turbine 44 when the vehicle 1 is traveling at high speed. 2).

  The torque converter 3 and the speed change mechanism 4 constitute an automatic transmission 5. The automatic transmission 5 changes the rotational speed of the crankshaft 41 to a desired rotational speed by forming a desired gear stage. The power output from the output gear of the automatic transmission 5 is transmitted to left and right front wheels (not shown) via a differential gear and a drive shaft (not shown). The transmission mechanism 4 will be described in detail later.

  The hydraulic control circuit 9 has linear solenoid valves SL1 to SL5. The hydraulic control circuit 9 has an oil temperature sensor 33 for measuring the oil temperature of the hydraulic oil.

  The engine ECU 11 has a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), and an input / output interface (not shown). The engine ECU 11 controls the number of revolutions of the engine based on a signal input from an accelerator sensor and a throttle sensor, which will be described later, a map stored in the ROM, and the like. Further, as will be described later, based on a command from the transmission ECU 12, torque-up control of the engine 2 during downshifting, that is, blipping is executed.

  The transmission ECU 12 has a CPU, a RAM, a ROM, and an input / output interface (not shown). The ROM of the transmission ECU 12 stores a map that associates the vehicle speed and throttle opening with the gear stage of the transmission mechanism 4. Therefore, the transmission ECU 12 determines the gear stage of the speed change mechanism by the CPU based on a signal input from a vehicle speed sensor or a throttle sensor described later and a map stored in the ROM.

  The transmission ECU 12 changes the operating state of the linear solenoid valves SL1 to SL5, and selectively engages or releases the friction engagement device of the speed change mechanism 4 with the operating hydraulic pressure using the line pressure PL as a source pressure. . The ratio of the rotational speed between the input shaft and the output shaft of the speed change mechanism 4 is changed by a combination of engagement and release of these friction engagement devices, and a gear stage is configured. Further, as will be described later, the transmission ECU 12 learns the engagement-side hydraulic pressure supplied to the engagement-side friction engagement device at the time of downshift, and corrects the engagement-side hydraulic pressure at the next downshift. It is like that.

  As will be described later, the transmission ECU 12 includes a shift control device, a torque-up control unit, a target time calculation unit, a hydraulic control unit, a shift end determination unit, an actual shift time measurement unit, a correction amount calculation unit, a learning, and the like. A value correction unit, an engagement time calculation unit, and a learning correction unit are configured.

  The vehicle 1 is further drawn into the engine 2 by an engine speed sensor 21 for detecting the output shaft speed NE of the engine 2, an intake air quantity sensor 22 for detecting the intake air quantity of the engine 2, and the engine 2. An intake air temperature sensor 23 for detecting the air temperature, a throttle sensor 24 for detecting the opening of the throttle valve 31, a vehicle speed sensor 25, and a cooling water temperature sensor 26 for measuring the cooling water temperature of the engine A brake sensor 27, an operation position sensor 29 for detecting the operation position of the shift lever 28, a turbine speed sensor 30 for detecting the turbine speed NT of the torque converter 3, an accelerator opening sensor 32, It has.

  The engine speed sensor 21 detects the speed of the engine 2 based on the rotation of the crankshaft 41.

  The throttle sensor 24 is constituted by, for example, a hall element that can obtain an output voltage corresponding to the throttle opening of the throttle valve 31. The throttle sensor 24 outputs this output voltage to the engine ECU 11 and the transmission ECU 12 as a signal representing the throttle opening of the throttle valve 31.

  The vehicle speed sensor 25 outputs a signal representing the output shaft rotational speed NO of the transmission mechanism 4 to the engine ECU 11 and the transmission ECU 12. The engine ECU 11 and the transmission ECU 12 calculate the vehicle speed based on this signal. It has become. In the present embodiment, the output shaft rotational speed of the speed change mechanism 4 refers to the rotational speed of the output gear 70 (see FIG. 2).

  The cooling water temperature sensor 26 is composed of, for example, a thermistor whose resistance value changes according to the water temperature, and outputs a signal based on the resistance value that changes according to the cooling water temperature of the engine 2 to the engine ECU 11 and the transmission ECU 12. It has become.

  The brake sensor 27 sends a signal (stepping force switch signal) that switches from an OFF state to an ON state when a brake pedal (not shown) provided in the vehicle 1 is depressed by a driver with a predetermined depression amount to the engine ECU 11 and the transmission ECU 12. It is supposed to send.

  The operation position sensor 29 detects the position of the shift lever 28 and transmits a signal representing the detection result to the transmission ECU 12. The transmission ECU 12 forms the gear stage of the speed change mechanism 4 that is optimal from the range corresponding to the position of the shift lever 28. Further, the operation position sensor 29 detects that the shift lever 28 is located at a manual position where the driver can select an arbitrary gear according to the operation of the driver.

  The turbine speed sensor 30 outputs a signal representing the turbine speed of the torque converter 3 to the engine ECU 11 and the transmission ECU 12, and the engine ECU 11 and the transmission ECU 12 based on this signal, that is, the turbine speed NT, that is, The input shaft rotation speed of the speed change mechanism 4 is detected.

  The accelerator opening sensor 32 is composed of, for example, an electronic position sensor using a hall element. When the accelerator pedal 34 mounted on the vehicle 1 is operated by the driver, the accelerator position indicated by the accelerator pedal 34 is indicated. A signal indicating the opening is output to the engine ECU 11.

  As shown in FIG. 2, the torque converter 3 is prevented from rotating in one direction by an impeller 43 connected to the crankshaft 41, a turbine 44 connected to the input shaft 48 of the transmission mechanism 4, and a one-way clutch 45. A stator 46. The impeller 43 and the turbine 44 transmit power via a fluid.

  The input shaft 48 of the transmission mechanism 4 is connected to the turbine 44 of the torque converter 3. Therefore, the input shaft 48 of the speed change mechanism 4 also functions as an output shaft of the torque converter 3. The transmission mechanism 4 includes a first set 50 of planetary gear mechanisms, a second set 60 of planetary gear mechanisms, an output gear 70, a B1 brake 72, a B2 brake 73 and a B3 brake 74 fixed to a gear case 71, and C1. The clutch 75, the C2 clutch 76, and the one-way clutch F77 are included.

  The first set 50 includes a single pinion type planetary gear mechanism. The first set 50 includes a sun gear S (UD) 51, a pinion gear 52, a ring gear R (UD) 53, and a carrier C (UD) 54.

  Sun gear S (UD) 51 is connected to turbine 44 of torque converter 3 via input shaft 48. The pinion gear 52 is rotatably supported by the carrier C (UD) 54. Pinion gear 52 is engaged with sun gear S (UD) 51 and ring gear R (UD) 53.

  The ring gear R (UD) 53 can be fixed to the gear case 71 by a B3 brake 74. Carrier C (UD) 54 can be fixed to gear case 71 by B1 brake 72.

  The second set 60 is constituted by a Ravigneaux type planetary gear mechanism. The second set 60 includes a sun gear S (D) 61, a short pinion gear 62, a carrier C (1) 63, a long pinion gear 64, a carrier C (2) 65, a sun gear S (S) 66, and a ring gear R. (1) (R (2)) 67.

  Sun gear S (D) 61 is connected to carrier C (UD) 54. The short pinion gear 62 is rotatably supported by the carrier C (1) 63. Short pinion gear 62 is engaged with sun gear S (D) 61 and long pinion gear 64. The carrier C (1) 63 is connected to the output gear 70.

  Long pinion gear 64 is rotatably supported by carrier C (2) 65. Long pinion gear 64 is engaged with short pinion gear 62, sun gear S (S) 66, and ring gear R (1) (R (2)) 67. The carrier C (2) 65 is connected to the output gear 70.

  The sun gear S (S) 66 can be connected to the input shaft 48 via the C1 clutch 75. The ring gear R (1) (R (2)) 67 can be fixed to the gear case 71 by the B2 brake 73, and can be connected to the input shaft 48 by the C2 clutch 76. Further, the ring gear R (1) (R (2)) 67 is connected to the one-way clutch F77, and the gear stage is at the first speed and cannot rotate during driving.

Next, the operation of the automatic transmission according to the embodiment of the present invention will be described with reference to the operation table of FIG.
In FIG. 3, “◯” represents engagement. “X” represents release. “◎” represents engagement only during engine braking. “Δ” represents engagement only during driving. By operating the brakes and the clutches by exciting and de-energizing linear solenoid valves SL1 to SL5 provided in the hydraulic control circuit 9 (see FIG. 1) and a transmission solenoid (not shown) in the combinations shown in the operation table. First to sixth forward gears and reverse gears are formed.

  In the present embodiment, when the automatic transmission 5 forms a fourth gear, the C1 clutch 75 and the C2 clutch 76 are engaged as shown in the operation table. From this state, for example, when the driver operates the shift lever 28 (see FIG. 1) to instruct a downshift to the third gear, the transmission ECU 12 controls the automatic transmission 5 to control the C2 clutch 76. Is released, and a re-holding for engaging the B3 brake 74 is executed.

  Therefore, in the downshift from the fourth speed to the third speed, the B3 brake 74 according to the present embodiment constitutes an engagement-side friction engagement device that is engaged during the downshift, and the C2 clutch 76 is the downshift. A release side frictional engagement device that is sometimes released is configured. Similarly, in a downshift between other shift speeds, the friction engagement device that shifts from the released state to the engaged state constitutes the engagement side frictional engagement device according to the present invention, and the engaged state is released from the engaged state. The frictional engagement device that shifts to constitutes the release-side frictional engagement device according to the present invention.

  The shift lever 28 (see FIG. 1) has a D position corresponding to a drive range (hereinafter simply referred to as a D range), an N position corresponding to a neutral range, and an R position corresponding to a reverse range from the rear to the front of the vehicle. The P position corresponding to the parking range is taken.

  When the shift lever 28 (see FIG. 1) is located in the D range, the gear stage forms one of the first to sixth gears. As described above, the transmission ECU 12 The gear stage is selected based on the vehicle speed and the throttle opening.

  The shift lever 28 (see FIG. 1) further includes an M position representing a manual position for shifting the gear stage of the automatic transmission 5 (see FIG. 1) in the manual shift mode, and a plus position (instruction for instructing an upshift). + Position) and minus position (− position) for instructing downshift. The M position is located beside the D position, and when the shift lever 28 (see FIG. 1) is moved laterally from the D position, it is held at the M position by a spring (not shown). .

Next, an outline of the hydraulic control circuit in the embodiment of the present invention will be described with reference to the circuit diagram of FIG.
As shown in FIG. 4, the hydraulic oil pumped from the oil pump 38 is regulated by a relief type regulator valve 40 to become a line pressure PL. The oil pump 38 is constituted by, for example, a mechanical pump that is rotationally driven by the engine 2.

  The hydraulic oil having the line pressure PL is supplied to the manual valve 39 that is interlocked with the shift lever 28 (see FIG. 1). When the shift lever 28 is positioned at a position corresponding to the forward range, hydraulic oil having a forward position pressure PD equal to the line pressure PL is supplied from the manual valve 39 to the linear solenoid valves SL1 to SL5. Yes.

  The linear solenoid valves SL1 to SL5 are arranged to correspond to the C1 clutch 75, the C2 clutch 76, the B1 brake 72, the B2 brake 73, and the B3 brake 74, respectively. The transmission ECU 12 adjusts the hydraulic pressures PC1, PC2, PB1, PB2, and PB3 by controlling these linear solenoid valves SL1 to SL5 with a solenoid current, and the C1 clutch 75, the C2 clutch 76, the B1 brake 72, and the B2 brake 73 are adjusted. , Switching the engagement and release of the B3 brake 74, and adjusting the engagement pressure.

  Hereinafter, a characteristic configuration of a vehicle 1 including a shift control device for an automatic transmission according to an embodiment of the present invention will be described with reference to FIG. In the following description, a case where the vehicle 1 is downshifted from the fourth gear to the third gear in response to a downshift instruction from the shift lever 28 will be described as an example.

  The turbine rotation speed sensor 30 detects the rotation speed of the input shaft 48 of the transmission mechanism 4. Therefore, the turbine rotation speed sensor 30 in the present embodiment constitutes the input rotation speed detection means in the present invention.

  The vehicle speed sensor 25 detects the rotational speed NO of the output gear 70 of the speed change mechanism 4. Therefore, the vehicle speed sensor 25 in the present embodiment constitutes an output rotation speed detection means in the present invention.

  The vehicle speed sensor 25 detects the speed of the vehicle 1 provided with the automatic transmission 5. Therefore, the vehicle speed sensor 25 in the present embodiment constitutes a vehicle speed detection means in the present invention.

  The operation position sensor 29 detects a signal indicating a downshift instruction when the shift lever 28 moves to the minus position. Therefore, the operation position sensor 29 in the present embodiment constitutes an instruction detection unit in the present invention.

When the transmission ECU 12 detects a signal representing a downshift instruction, the transmission ECU 12 transmits a torque up execution instruction to the engine ECU 11 so that the engine 2 executes torque up.
Therefore, the transmission ECU 12 in the present embodiment constitutes a torque up control means in the present invention.

Further, the transmission ECU 12 calculates a target shift time optimum for shifting according to the gear stage selected by the downshift instruction and the vehicle speed. Specifically, when the transmission ECU 12 obtains a detection signal indicating that the shift lever 28 has moved to the minus position from the operation position sensor 29, the transmission ECU 12 calculates an instruction shift stage that is shifted down by one step from the current gear stage stored, The target shift time corresponding to the vehicle speed detected by the detection signal acquired from the vehicle speed sensor 25 is calculated with reference to a later-described target shift time setting map (see FIG. 6) corresponding to the indicated shift speed. .
Therefore, the transmission ECU 12 in the present embodiment constitutes a target time calculation means in the present invention.

Further, the transmission ECU 12 detects the signal indicating the downshift instruction, and when the engagement start time corresponding to the set target shift time has elapsed, the hydraulic pressure supplied to the engagement side frictional engagement device is the torque capacity. It is designed to meet the requirements. Specifically, when the transmission ECU 12 detects a signal indicating a downshift instruction, the transmission ECU 12 immediately decreases the hydraulic pressure PC2 with respect to the C2 clutch 76 constituting the disengagement side frictional engagement device, and when the engagement start time comes, The engagement pressure PB3 with respect to the B3 brake 74 constituting the combined friction engagement device is increased to synchronize the turbine speed NT and the output gear speed NO. At this time, the transmission ECU 12 corrects the engagement start time based on a shift control process (see FIG. 7) described later.
Therefore, the transmission ECU 12 in the present embodiment constitutes a hydraulic control means in the present invention.

Further, the transmission ECU 12 determines the end of the shift by synchronizing the turbine rotational speed NT and the output gear rotational speed NO. Specifically, the transmission ECU 12 determines the turbine rotational speed NT detected by the turbine rotational speed sensor 30 based on the gear ratio of the indicated shift speed set in the specification values of the vehicle 1 stored in advance, the vehicle speed It is determined whether or not the output gear rotation speed NO detected by the sensor 25 is synchronized. For example, when downshifting from the 4th speed to the 3rd speed, if the gear ratio of the 3rd speed is "1.42", the turbine speed NT is "1.42" times the output gear speed NO. The rotation speed is synchronized, and it is determined that the shift has been completed.
Therefore, the transmission ECU 12 in the present embodiment constitutes a shift end determination means in the present invention.

Further, the transmission ECU 12 measures an actual shift time from detection of a downshift instruction to determination of completion of shift of the automatic transmission 5. Specifically, the transmission ECU 12 starts timing by a timer from detection of a downshift instruction by acquiring a detection signal that the shift lever 28 has moved to the minus position from the operation position sensor 29, and the shift of the automatic transmission 5 is completed. The actual speed change time is measured by measuring the time until determination.
Therefore, the transmission ECU 12 in the present embodiment constitutes an actual shift time measuring means in the present invention.

Further, the transmission ECU 12 calculates a correction amount of the engagement start time based on the actual shift time and the target shift time calculated as described above, and learns and corrects the engagement start time. Further, the transmission ECU 12 performs learning correction so that the engagement start time is delayed when the actual shift time is shorter than the target shift time, and the engagement start time is advanced when the actual shift time is longer than the target shift time. So that learning is corrected. Furthermore, the transmission ECU 12 can calculate a correction amount of the torque increase request amount based on the target shift time and the actual shift time, and can also learn and correct the torque increase request amount at the time of torque increase.
Therefore, transmission ECU12 in this Embodiment comprises the learning correction | amendment means in this invention.

Further, the transmission ECU 12 calculates a correction amount for the engagement start time. Further, the transmission ECU 12 corrects the learning value for calculating the engagement start time from the target shift time based on the correction amount. Further, the transmission ECU 12 calculates the engagement start time from the target shift time based on the corrected learning value.
Therefore, the transmission ECU 12 in the present embodiment constitutes a correction amount calculation means, a learning value correction means, and an engagement time calculation means in the present invention.

  Next, the control timing of the transmission ECU according to the embodiment of the present invention will be described with reference to the timing chart of FIG.

  Here, the graph (a) represents the change in the instructed gear stage that is instructed by the shift lever 28. Graph (b) represents the change in turbine speed NT during downshifting. Graph (c) represents a change in the engagement side hydraulic pressure, and in the present embodiment, a change in the engagement pressure PB3 with respect to the B3 brake 74. Further, the graph (d) represents a change in the requested torque-up amount requested from the engine 2 by the transmission ECU 12 via the engine ECU 11. Graph (e) represents the change in turbine speed NT when the torque-up request amount is changed.

  First, the case where the target shift time is (T6-T0) time and the shift is completed at time T6, which is the optimal shift time, will be described. Further, it is assumed that the downshift from the fourth speed to the third speed is performed.

  The transmission ECU 12 determines that the shift lever 28 has moved to the minus position by the operation position sensor 29 at time T0, thereby determining a downshift, and changes the instructed gear stage from the fourth speed to the third speed (graph ( a)). Further, the transmission ECU 12 promptly reduces the disengagement hydraulic pressure supplied to the C2 clutch 76 to “0” in accordance with the downshift instruction. At the same time, the transmission ECU 12 starts timing by a timer. Furthermore, the transmission ECU 12 acquires a signal representing the vehicle speed from the vehicle speed sensor 25.

  Next, the transmission ECU 12 requests the engine ECU 11 to increase the torque of the engine 2 at time T1 (see graph (d)). Specifically, the transmission ECU 12 calculates the torque-up request amount by referring to the torque-up request amount stored in advance in the ROM on the basis of the parameters such as the instructed shift speed and the current vehicle speed. Yes. Then, the transmission ECU 12 transmits a signal indicating the calculated torque increase request amount to the engine ECU 11.

  When the engine ECU 11 acquires a signal indicating the torque increase request amount, the engine ECU 11 controls the opening degree of the throttle valve 31 in accordance with the torque increase request amount, and increases the torque amount output from the engine 2. At this time, the actual torque amount actually output from the engine 2, that is, the engine torque Te fluctuates due to individual differences of the vehicle 1 and changes in the travel environment.

The transmission ECU 12 increases the turbine rotation speed NT by the actual torque generated by the torque increase request (see graph (b)), and advances the downshift.
Further, the transmission ECU 12 makes this torque increase request until the turbine rotational speed NT and the output gear rotational speed NO are synchronously rotated. Specifically, the transmission ECU 12 synchronizes the turbine rotational speed NT detected by the turbine rotational speed sensor 30 and the output gear rotational speed NO detected by the vehicle speed sensor 25 based on the gear ratio of the instructed gear. It is determined whether or not.
Further, the transmission ECU 12 increases the engagement side hydraulic pressure to a predetermined first fill pressure, and rapidly fills the hydraulic oil (see graph (c)).

  Next, the transmission ECU 12 holds the engagement-side hydraulic pressure at a predetermined constant pressure standby pressure at time T2 (see graph (c)). Here, the constant pressure standby pressure is a hydraulic pressure that is brought into a completely released state immediately before the B3 brake 74 is engaged. Here, the transmission ECU 12 advances the downshift while the B3 brake 74 is in the released state.

  On the other hand, when the transmission ECU 12 detects the downshift instruction, the transmission ECU 12 also calculates the engagement start time. Specifically, the transmission ECU 12 calculates a target shift time corresponding to the designated shift speed, and calculates an engagement start time corresponding to the calculated target shift time. For example, if the target shift time is time T6 (see graph (a)), the corresponding engagement start time is time T5 (see graph (c)). Details of the calculation of the engagement start time will be described later.

  The transmission ECU 12 determines that the engagement start time has come at time T5, and starts control of the engagement side hydraulic pressure. Specifically, the transmission ECU 12 increases the engagement side hydraulic pressure supplied to the B3 brake 74 until the B3 brake 74 is completely engaged. Here, the degree of increase in the engagement-side hydraulic pressure under the control of the transmission ECU 12 may vary from vehicle to vehicle even with the same specification. Therefore, even if the engagement start time is the same, the actual shift time until the actual shift ends varies depending on the vehicle. The actual shift time is optimized by learning and correcting the engagement start time by a shift control process described later.

Next, when the transmission ECU 12 determines that the turbine rotation speed NT and the output gear rotation speed NO have reached synchronous rotation and the shift has been completed at time T6, the transmission ECU 12 acquires the current time and calculates the actual shift time. To do.
The transmission ECU 12 calculates an engagement start learning value based on the actual shift time and the target shift time acquired in the current shift control, and stores them in the RAM. Furthermore, transmission ECU12 correct | amends the engagement start time in the next downshift according to the engagement start learning value memorize | stored in RAM.

  Further, as shown by the dotted line in FIG. 5, when the engagement start time is time T6 later than the optimum engagement start time T5 (see graph (c)), the shift end time is time T8 (graph (a )reference). In this case, since the actual shift time is (T8-T0), the engagement start learning value (T6-T5) is calculated based on the difference (T8-T6) from the target shift time (T6-T0). The engagement start time can be corrected from T6 to T5.

  Similarly, as indicated by the one-dot chain line in FIG. 5, when the engagement start time is time T3 earlier than the optimum engagement start time T5 (see graph (c)), the shift end time is time T4 (graph). (See (a)). In this case, since the actual shift time is (T4-T0), the engagement start learning value (T3-T5) is calculated based on the difference (T4-T6) from the target shift time (T6-T0). The engagement start time can be corrected from T3 to T5.

  Further, the engine torque TE may be controlled to optimize the shift time. As shown by a two-dot chain line in FIG. 5, it is assumed that the shift end time is a time T7 later than the optimal shift end time T6 (see graph (e)). In this case, since the actual shift time is (T7-T0), the torque-up request amount is changed based on the difference (T7-T6) from the target shift time (T6-T0) (see graph (d)). . Thereby, since the variation | change_quantity of turbine rotation speed NT changes (refer graph (e)), shift end time can be made into the optimal time T6.

  Next, FIG. 6 shows a target shift time setting map in the embodiment of the present invention and will be described.

  The target shift time setting map associates the vehicle speed with the target shift time for each shift stage, and is stored in advance in the ROM of the transmission ECU 12. The target shift time setting map is set and stored separately for upshift and downshift.

  The transmission ECU 12 displays a map for each gear stage downshift and a map for each gear stage upshift in addition to the map for three-speed downshift shown in FIG. 6 (a) and the map for four-speed downshift shown in FIG. 6 (b). It is stored in ROM.

  When the shift lever 28 is moved and the operation position sensor 29 acquires the gear shift instruction, or the transmission ECU 12 determines that the automatic gear shift is performed according to the running state, the transmission ECU 12 acquires the target gear shift time from the map corresponding to the gear shift instruction stage.

  In addition, the ROM of the transmission ECU 12 has a start time calculation value for obtaining a reference engagement start time for starting to apply hydraulic pressure to the engagement side frictional engagement device so that the shift is completed at the target shift time for each shift stage. It is remembered. The calculated start time may be stored together with the target shift time in the target shift time setting map.

  Next, FIG. 7 shows a flowchart of the shift control process in the embodiment of the present invention, and the operation will be described.

  Note that the flowchart shown in FIG. 7 represents the execution contents of a shift control process program executed by the transmission ECU 12. The shift control processing program is stored in the ROM of the transmission ECU 12 and is executed at predetermined time intervals. Note that this shift control processing is performed in place of a shift instruction determination of the vehicle 1 (step S11) or a shift instruction determination (step S11) and a downshift determination (step S12) described later, Alternatively, it may be executed when a downshift is detected.

  Further, it is assumed that the current gear is stored in advance in the RAM of the transmission ECU 12. Furthermore, it is assumed that an engagement start learning value for performing learning correction of the engagement start time is calculated and stored in the previous shift process in the RAM of the transmission ECU 12.

As shown in FIG. 7, first, the transmission ECU 12 determines whether or not a shift instruction has been issued (step S11). Specifically, the transmission ECU 12 determines whether or not a shift position signal, which is position information of the shift lever 28, is input based on a detection signal input via the operation position sensor 29, and acquires a new shift position signal. In this case, it is determined that there is a shift instruction.
If the transmission ECU 12 determines that a shift instruction has not been issued (NO in step S11), the shift control process ends.

If the transmission ECU 12 determines that a shift instruction has been issued (YES in step S11), the transmission ECU 12 determines whether or not it is a downshift instruction (step S12). If it is not a downshift instruction (NO in step S12). (Determination), and this shift control process is terminated.
Specifically, the transmission ECU 12 determines that it is a downshift instruction if the acquired shift position signal is a detection signal indicating a minus position (-position).

  If the transmission ECU 12 determines that the instruction is a downshift instruction (YES in step S12), the transmission ECU 12 starts measuring the shift time (step S13). Specifically, the transmission ECU 12 starts timing by a timer. In addition, when the downshift instruction is input, the transmission ECU 12 sets the gear stage, which is one step lower than the current gear stage stored in the RAM, as the designated shift stage. For example, if the current gear stage stored in the RAM is the fourth speed, the transmission ECU 12 sets the designated gear stage to the third speed.

  Next, the transmission ECU 12 makes a torque increase request to the engine ECU 11 (step S14). Specifically, the transmission ECU 12 sends a torque-up request to the engine ECU 11 together with the instructing gear stage. When the engine ECU 11 receives a torque-up request by downshifting from the transmission ECU 12, the engine ECU 11 calculates a torque-up amount corresponding to the command shift speed and the current vehicle speed based on an engine torque map stored in the ROM in advance. Control is performed so that the torque of the engine 2 increases.

  Next, the transmission ECU 12 prepares the engagement side hydraulic pressure of the engagement side frictional engagement device (step S15). Specifically, the transmission ECU 12 raises the hydraulic pressure of the target friction engagement device to a predetermined first fill pressure, rapidly fills the hydraulic oil, and then maintains the predetermined constant pressure standby pressure. 9 is controlled. For example, when downshifting from the 4th speed to the 3rd speed, the hydraulic pressure PB3 is raised to the above-mentioned first fill pressure with respect to SL5 that controls the hydraulic pressure PB3 of the B3 brake 74 and then held at a constant pressure standby pressure. Control to do. Here, the constant pressure standby pressure is a hydraulic pressure that is brought into a completely released state immediately before the B3 brake 74 is engaged.

  Next, the transmission ECU 12 calculates a target shift time that is an optimal shift time until the shift is completed (step S16). Specifically, the transmission ECU 12 acquires the above-described target shift time setting map corresponding to the instructed shift speed, and calculates the target shift time based on the current vehicle speed.

  Next, the transmission ECU 12 calculates a reference engagement start time, and corrects the engagement start time based on the engagement start learning value (step S17). Specifically, the transmission ECU 12 acquires the above-described calculated start time value corresponding to the shift instruction stage, and calculates a reference engagement start time from the calculated target shift time. Further, the engagement start learning value stored in the past shift is added to the calculated reference engagement start time to calculate the engagement start time (engagement start time = reference engagement start time + engagement). Start learning value).

  Next, the transmission ECU 12 determines whether or not the engagement start time has been reached (step S18), and if it has not reached the engagement start time (determined as NO in step S18), the current state until the engagement start time is reached. Continue control.

  If it is determined that the engagement start time has come (YES in step S18), the transmission ECU 12 starts control of the engagement side hydraulic pressure (step S19). Specifically, the transmission ECU 12 increases the hydraulic pressure of the target friction engagement device and increases it to a hydraulic pressure at which the friction engagement device is completely engaged. For example, when downshifting from the fourth speed to the third speed, the hydraulic pressure PB3 is controlled to gradually increase so that the B3 brake 74 is completely engaged with the SL5 that controls the hydraulic pressure PB3 of the B3 brake 74. To do.

  Next, the transmission ECU 12 determines whether or not the rotation of the input / output shaft is synchronized (step S20). If the rotation of the input / output shaft is not synchronized (determined as NO in step S20), the transmission ECU 12 performs synchronous rotation. Until the current control continues. Specifically, the transmission ECU 12 synchronizes the turbine rotational speed NT detected by the turbine rotational speed sensor 30 and the output gear rotational speed NO detected by the vehicle speed sensor 25 based on the gear ratio of the instructed gear. It is determined whether or not. For example, when downshifting from the 4th speed to the 3rd speed, when the gear ratio of the 3rd speed is "1.42," the turbine speed NT is "1.42" times the output gear speed NO. It is determined that the rotation speed is synchronized.

  If the transmission ECU 12 determines that the rotation of the input / output shaft is synchronized (YES in step S20), the transmission ECU 12 acquires the actual shift time (step S21). Specifically, the timer measures the time from the start of the shift time measurement at the time of downshift determination (step S13) to the determination of the synchronous rotation of the input / output shaft (step S20), and acquires this time.

  Next, the transmission ECU 12 calculates a correction amount for the engagement start learning value from the target shift time and the actual shift time (step S22). Specifically, the transmission ECU 12 calculates a difference (target shift time-actual shift time) between the target shift time and the detected actual shift time, and sets a value corresponding to this difference as the engagement start learning value. The correction amount.

  For example, the transmission ECU 12 can directly set the difference between the actual shift time and the target shift time as the correction amount of the engagement start learning value. Thus, the transmission ECU 12 performs learning correction so that the engagement start time is delayed when the actual shift time is shorter than the target shift time, and when the actual shift time is longer than the target shift time, the engagement start time Can be corrected so as to be faster.

  Further, the transmission ECU 12 can also use a value obtained by multiplying a predetermined ratio according to the difference between the target shift time and the actual shift time as the correction amount of the engagement start learning value. Thus, by multiplying the predetermined ratio, learning correction of the engagement start time can be performed with higher accuracy.

  Next, the transmission ECU 12 learns and corrects the engagement start learning value with the calculated correction amount (step S23), and ends the shift control process. Specifically, the transmission ECU 12 adds the correction amount calculated in the current shift process to the engagement start learning value (“next“ engagement start learning value = “current“ engagement start learning value + ”). The "correction amount" calculated this time, the start timing of the engagement side hydraulic pressure at the next shift is learned, the shift time is optimized, and the drivability at the shift is improved.

  Further, when the transmission ECU 12 changes the engine torque amount and controls the shift time, in step S17, the transmission ECU 12 acquires a torque-up request amount corresponding to the shift instruction stage based on a preset torque map, A reference torque increase amount is calculated from the calculated target shift time. Further, the torque increase request amount is calculated by adding the engagement start learning value stored in the past shift to the calculated reference torque increase amount. In this case, the engagement start learning value is a learning value for calculating the torque-up request amount.

  Further, in step S22 and step S23, the transmission ECU 12 calculates the correction amount of the engagement start learning value for calculating the torque increase request amount from the target shift time and the actual shift time, and this correction amount. The learning start learning value is corrected by learning.

  As described above, in the shift control device for an automatic transmission according to the embodiment of the present invention, the actual shift time required for the actual shift is measured, and the engagement is performed based on the actual shift time and the target shift time. Since the start time is learned and corrected, the engagement timing of the friction engagement device can be set to an engagement timing suitable for the actual vehicle 1, and the engagement start time for increasing the engagement-side hydraulic pressure is corrected for learning. Since the shift time can be optimized only by setting the engagement start time, the learning accuracy of the shift time can be improved by simple control, and the drivability during the shift can be improved.

  In addition, since the shift control device for the automatic transmission according to the present embodiment performs learning correction on the engagement start time corresponding to the target shift time corresponding to the gear stage and vehicle speed at the time of shift, learning according to the situation at the time of shift And the learning accuracy of the shift time can be improved.

  Further, the shift control device for the automatic transmission according to the present embodiment performs learning correction so that the engagement start time is delayed when the actual shift time is shorter than the target shift time, and the engagement start time is earlier when the actual shift time is shorter. Therefore, since the engagement start time can be controlled to an optimum value, the engagement timing suitable for the actual vehicle 1 can be set, and learning accuracy of the shift time can be improved with simple control, and Drivability can be improved.

  Furthermore, since the shift control device of the automatic transmission according to the present embodiment corrects the torque amount at the time of torque increase by the actual shift time, the change amount of the turbine rotation speed NT can be changed, and the turbine rotation speed NT is For example, the time itself approaching the output gear rotational speed NO can be changed, so that the range of control can be expanded and the learning accuracy of the shift time can be increased.

  In the above description, the case where the shift control device for an automatic transmission according to the present invention is applied to a vehicle equipped with an engine as a power source has been described. However, the shift control device for an automatic transmission according to the present invention may be applied to a vehicle equipped with a motor generator as a power source, or a vehicle equipped with an engine and a motor generator.

  The embodiment disclosed this time is illustrative in all respects and is not limited to this embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of the claims, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

  As described above, the shift control device for an automatic transmission according to the present invention has an effect that the learning accuracy of the shift time can be improved by simple control and the drivability during the shift can be improved. This is useful as a shift control device for an automatic transmission that executes torque-up of a power source during a shift.

1 vehicle 2 engine (power source)
3 Torque converter 4 Transmission mechanism 5 Automatic transmission 9 Hydraulic control circuit 11 Engine ECU
12 transmission ECU (shift control device, torque up control means, target time calculation means, hydraulic pressure control means, shift end determination means, actual shift time measurement means, learning correction means, correction amount calculation means, learning value correction means, engagement time Calculation means)
DESCRIPTION OF SYMBOLS 21 Engine speed sensor 22 Intake air amount sensor 23 Intake air temperature sensor 24 Throttle sensor 25 Vehicle speed sensor (output speed detection means, vehicle speed detection means)
26 Cooling water temperature sensor 27 Brake sensor 28 Shift lever 29 Operation position sensor (instruction detection means)
30 Turbine speed sensor (input speed detection means)
31 Throttle valve 33 Oil temperature sensor 41 Crankshaft 43 Impeller 44 Turbine 48 Input shaft 50 First set 60 Second set 70 Output gear 71 Gear case 72 B1 brake 73 B2 brake 74 B3 brake (engagement side friction engagement device)
75 C1 clutch 76 C2 clutch (release side frictional engagement device)

Claims (4)

An automatic transmission having a transmission mechanism connected to a power source via an input shaft and configured to establish a plurality of gear stages having different transmission gear ratios by selectively engaging a plurality of hydraulic friction engagement devices. On the other hand, a shift control for downshift that releases a predetermined disengagement-side frictional engagement device among the plurality of hydraulic engagement devices, while engaging a predetermined engagement-side frictional engagement device and torque-up the power source. In a shift control device for an automatic transmission that executes
Input rotation speed detection means for detecting the rotation speed of the input shaft of the speed change mechanism;
Output rotation speed detecting means for detecting the rotation speed of the output shaft of the speed change mechanism;
Instruction detection means for detecting an instruction of the downshift;
Torque up control means for executing torque up for the power source triggered by detection of a downshift instruction by the instruction detection means, and controlling a torque amount in the torque up;
When an engagement start time corresponding to a preset target shift time has elapsed since the detection of the downshift instruction, control is performed so that the engagement side hydraulic pressure supplied to the engagement side frictional engagement device satisfies the torque capacity. Hydraulic control means;
Shift end determination means for determining end of shift of the automatic transmission by synchronizing the rotation speed of the input shaft and the rotation speed of the output shaft;
An actual shift time measuring means for measuring an actual shift time from detection of the downshift instruction to determination of shift completion of the automatic transmission;
Learning correction means for calculating a correction amount of the engagement start time based on the target shift time and the actual shift time, and learning correcting the engagement start time;
A shift control device for an automatic transmission, comprising: Vehicle speed detecting means for detecting the speed of a vehicle equipped with the automatic transmission;
Target time calculation means for calculating the target shift time according to the gear selected by the downshift instruction and the detected vehicle speed,
The learning correction means includes a correction amount calculation means for calculating the correction amount, a learning value correction means for correcting a learning value for calculating the engagement start time from the target shift time based on the correction amount, and the corrected The shift control device for an automatic transmission according to claim 1, further comprising an engagement time calculation unit that calculates the engagement start time from the target shift time based on a learned value.   The learning correction means performs learning correction so that the engagement start time is delayed when the actual shift time is shorter than the target shift time, and when the actual shift time is longer than the target shift time, 3. The shift control apparatus for an automatic transmission according to claim 1, wherein learning correction is performed so that the combined start time becomes earlier.   The learning correction means calculates a correction amount of the torque amount controlled by the torque up control means based on the target shift time and the actual shift time, and learns and corrects the torque amount at the time of the torque increase. The shift control device for an automatic transmission according to any one of claims 1 to 3, characterized in that: