JP4978727B2 - Control device for automatic transmission, control method, program for causing computer to realize the method, and recording medium recording the program - Google Patents

Description

  The present invention relates to a control device for an automatic transmission, and more particularly to control for completing a shift requiring switching of two or more friction engagement elements in a short time while suppressing a shift shock.

  The components of the automatic transmission of the vehicle include a planetary gear composed of rotating elements such as a sun gear, a ring gear, and a planetary gear, and a friction engagement element. In such an automatic transmission, by switching the combination of the friction engagement elements to be engaged (also referred to as “replacement” in the following description), the path through which the torque from the engine is transmitted is switched to Are formed. In particular, in an automatic transmission with many gears (for example, a 6-speed automatic transmission), a plurality of clutch elements as input elements and a plurality of brake elements as reaction force elements are provided.

  In such an automatic transmission, when shifting to a gear stage separated from the current gear stage by a plurality of gears due to a shifting operation or an acceleration request, the input element and the reaction force element may be switched for shifting. is there. In this case, one of the input element and the reaction force element is switched, and after passing through the intermediate gear stage, the other is switched to change the speed.

  Such shift control for switching in two steps via an intermediate gear is known. For example, in WO2003 / 029699 (Patent Document 1), a gear change intention is changed after a driver is prohibited from changing a target gear stage at the time of a shift that achieves a shift by performing a plurality of switching controls. Disclosed is a shift control device for an automatic transmission that can quickly respond to a request and smoothly achieve double switching control even when a shift to a certain gear is requested. This shift control device is a shift control device for an automatic transmission provided with shift control means for achieving a plurality of forward gears by controlling engagement / release of a plurality of friction elements involved in the shift of the automatic transmission. The speed change control device releases at least the first friction element and the second friction element from the Nth speed stage achieved by setting at least the first friction element and the second friction element to the engaged state, This is achieved by fastening the third friction element and the fourth friction element, and at least achieved by fastening the second friction element and the third friction element between the Nth speed stage. A double change gear shift determining means for determining a shift to the N-α speed stage having one or more intermediate gear stages, and at the time of the double change gear shift determination, at least the first friction element is released; Before the gear ratio reaches the gear ratio corresponding to the intermediate gear stage, the fastening force of the second friction element is reduced, and after the gear ratio passes the gear ratio corresponding to the intermediate gear stage, at least By releasing the second friction element and fastening the third friction element A jump shift control means for achieving a shift from the Nth speed to the N-α speed, and a target gear stage at a predetermined timing after the start of the shift when performing a shift from the Nth speed to the N-α speed. The target shift speed change prohibiting means for determining that the change from the N-αth speed is prohibited until the end of the shift control, and when the gear ratio reaches a gear ratio corresponding to the intermediate gear, When the target gear stage is different from the N-α stage, even if the change of the target gear stage is prohibited, the target gear stage to the gear stage according to the driver's intention is changed. And a target gear stage change permission means for permitting the change.

  According to the shift control device for an automatic transmission disclosed in the above-mentioned publication, a short shift can be achieved when the driver intends to change the gear stage, and the driver intends to change the gear stage. If not, the H / C hydraulic pressure is reduced before reaching the gear ratio equivalent to the fifth gear, so that the shift is not fixed and a plurality of shift shocks are not generated in double switching. When the driver does not intend to change, smooth double change gear shifting can be achieved.

WO2003 / 029699

  However, in the speed change control device disclosed in the above-mentioned publication, when the gear ratio reaches a gear ratio corresponding to the intermediate gear stage during the shift of a plurality of gear stages, the shift control apparatus disclosed in the above publication is in accordance with the shift intention of the driver. In this case, the shift to the target gear stage is prohibited, but if the driver's intention does not change, the control to change to the target gear stage is performed after the intermediate gear stage is formed. That is, after the first friction element is changed to the fourth friction element and the intermediate gear stage is completely formed, the second friction element is changed to the third friction element. For this reason, the period of the shifting operation may become long.

  When the first friction element and the second friction element are switched in parallel, the third friction element and the fourth friction element are released after the first friction element and the second friction element are released. Since there is a rotating element in which the number of rotations cannot be detected in the automatic transmission until the friction element is engaged, a shift shock may occur when the third friction element and the fourth friction element are engaged. .

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control device, control method, and control for an automatic transmission that improves the response of a shift and prevents a shift shock. An object is to provide a program for causing a computer to execute the method, and a recording medium on which the program is recorded.

  In the control device for an automatic transmission according to the first invention, the first friction element and the second friction element are engaged with each other to form the first gear stage, and the first friction element and the second friction element This is a control device for an automatic transmission in which a second gear stage is formed by engagement of a third friction element and a fourth friction element, which are different from the above friction elements. The control device includes a first release for reducing the engagement force of the first friction element so that the first friction element is released when shifting from the first gear stage to the second gear stage. A control means, a semi-engagement control means for reducing the engagement force of the second friction element so as to obtain a predetermined engagement force with the release of the first friction element, The first engagement control means for increasing the engagement force of the third friction element at the time point 1 and the second friction element are released so that the second friction element is released together with the engagement of the third friction element. A second release control means for further reducing the engagement force of the friction element, and a second engagement for increasing the engagement force of the fourth friction element at a second time point later than the first time point. Control means. The control method for the automatic transmission according to the eleventh invention, the program realized by the computer according to the twelfth invention, and the recording medium according to the thirteenth invention are the same as the control device for the automatic transmission according to the first invention. It has a configuration.

  According to the first invention, in the first friction element and the second friction element forming the first gear stage, the first friction element is released, and the second friction element has a predetermined engagement force. It is released so as to be in a semi-engaged state. Since the third friction element is engaged at the first time point while the second friction element remains in the half-engaged state, the state is close to the intermediate gear stage here. At this time, the second friction element is released, and the fourth friction element is engaged at the second time point, whereby the second gear stage is formed. In this way, the engagement force of both the first friction element and the second friction element is controlled simultaneously, and the third friction element and the fourth friction element are engaged at the first time point and the second time point. Thus, the intermediate gear stage is completely formed as compared with the case where the switching between the second friction element and the third friction element and the switching between the first friction element and the fourth friction element are performed stepwise. Therefore, the speed change operation can be completed in a short time. Since it is not necessary to completely form the intermediate gear stage, the change in the engine speed does not stagnate during the shift. Therefore, the responsiveness of the shift is improved. Further, for example, when the time point synchronized with the intermediate gear stage formed by the second friction element and the third friction element is the first time point, the third friction element is engaged at the first time point. Thus, a shift shock at the time of engagement of the third friction element can be suppressed. In addition, when the time point synchronized with the second gear stage is the second time point, the shift shock at the time of engagement of the fourth friction element is suppressed by engaging the fourth friction element at the second time point. can do. Therefore, it is possible to provide a control device for an automatic transmission that improves the responsiveness of shift and prevents shift shock. The control method for the automatic transmission according to the eleventh invention, the program realized by the computer according to the twelfth invention, and the recording medium according to the thirteenth invention are the same as the control device for the automatic transmission according to the first invention. Has an effect.

  In the control device for an automatic transmission according to the second invention, in addition to the configuration of the first invention, the predetermined engagement force is applied after the third friction element starts engaging. Until this is the engaging force that restricts the rotating element of the automatic transmission and causes the second friction element to slip when torque is transmitted via the rotating element when the rotating element is engaged.

  According to the second invention, before the engagement of the third friction element is started, the second friction element is engaged with a predetermined engagement force, so that the rotation element of the automatic transmission is restricted. It will be in the state. Therefore, the automatic transmission can be brought into a state close to the intermediate gear stage by engaging the third friction element at the first time point. Further, when the third friction element is engaged, slippage occurs in the second friction element, so that the rotation of the rotation element of the automatic transmission is formed by the second friction element and the third friction element. It is possible to prevent the rotational speed from being synchronized with the intermediate gear stage. Thereby, the output shaft rotation speed of the automatic transmission can be changed without stagnation in the synchronous rotation speed of the intermediate gear stage. Therefore, the fourth friction engagement element can be engaged with the rotation speed synchronized with the second transmission gear stage, so that the responsiveness of the shift operation can be improved.

  In the automatic transmission control apparatus according to the third invention, in addition to the configuration of the first or second invention, the automatic transmission includes a fluid coupling in which an input shaft is connected to a power source, and an output shaft of the fluid coupling. And a transmission mechanism connected to the. The first time point is substantially the same time point when the input shaft rotation speed of the speed change mechanism becomes the rotation speed synchronized with the intermediate gear stage formed by the engagement of the second friction element and the third friction element. .

  According to the third invention, the third friction element is engaged at substantially the same time as the rotation speed synchronized with the intermediate gear stage formed by the engagement of the second friction element and the third friction element. In this case, the third friction element can be engaged with the automatic transmission close to the intermediate gear stage. Therefore, it is possible to suppress the occurrence of a shift shock when the third friction element is engaged.

  In the automatic transmission control apparatus according to the fourth aspect of the invention, in addition to the configuration of the third aspect of the invention, the first time point is intermediate from the time point when the first friction element or the second friction element is released. This is the time when the set time corresponding to the time of synchronization with the gear stage has elapsed.

  According to the fourth aspect of the invention, when the third friction element is engaged when the set time has elapsed from the time when the first friction element or the second friction element is released, the set time becomes the intermediate gear stage. Since the automatic transmission is close to the intermediate gear stage, the third friction element can be engaged. Therefore, it is possible to suppress the occurrence of a shift shock when the third friction element is engaged.

  According to a fifth aspect of the present invention, there is provided a control device for an automatic transmission, in addition to the configuration of any one of the first to fourth aspects of the invention, a first detection means for detecting the input shaft rotational speed of the fluid coupling, and a fluid coupling And second learning means for detecting the output shaft rotational speed, and learning means for learning the first time point based on the input shaft rotational speed and the output shaft rotational speed.

  According to the fifth aspect of the present invention, when shifting from the first gear stage to the second gear stage, depending on the time point when the third friction element is engaged, it rotates between the input shaft and the output shaft of the fluid coupling. There may be a number difference. This is because the input shaft rotation speed of the transmission mechanism (that is, the output shaft rotation speed of the fluid coupling) is delayed when the third friction element is engaged after being synchronized with the intermediate gear stage. This occurs in order to reduce the rotational speed so that the rotational speed is synchronized with the intermediate gear. At this time, a positive torque is generated in the transmission mechanism, and a shift shock is generated. Therefore, if learning is performed by advancing the first time point based on the input shaft speed and the output shaft speed of the fluid coupling, the third friction element can be engaged at an appropriate time. Therefore, it is possible to suppress the occurrence of shift shock when the third friction element is engaged and perform a smooth shift operation.

  In the automatic transmission control apparatus according to the sixth invention, in addition to the configuration of the fifth invention, the learning means calculates the first time point based on the difference between the input shaft rotation speed and the output shaft rotation speed. Includes means for learning.

  According to the sixth aspect, the slip amount of the fluid coupling can be detected based on the difference between the input shaft rotational speed and the output shaft rotational speed. Therefore, it is possible to detect a decrease in the output shaft rotational speed of the fluid coupling during a shift from the first gear stage to the second gear stage. Therefore, by learning the first time point based on the difference between the input shaft rotation speed and the output shaft rotation speed of the fluid coupling (for example, if the first time point is advanced when the difference is large), an appropriate time point is obtained. The third friction element can be engaged. Therefore, it is possible to suppress the occurrence of shift shock when the third friction element is engaged and perform a smooth shift operation.

  In the automatic transmission control device according to the seventh aspect of the invention, in addition to the configuration of the sixth aspect of the invention, the learning means increases the difference between the input shaft rotational speed and the output shaft rotational speed as the first time point increases. Includes means to learn early.

  According to the seventh invention, the greater the difference between the input shaft rotational speed and the output shaft rotational speed, the greater the slip amount of the fluid coupling. When shifting from the first gear stage to the second gear stage, the amount of reduction in the output shaft rotational speed of the fluid coupling increases as the engagement of the third friction element is delayed from the point of time synchronized with the intermediate gear stage. Therefore, the amount of slip increases. Therefore, the larger the difference between the input shaft rotational speed and the output shaft rotational speed, the faster the first time point is learned, thereby engaging the third friction element at an appropriate time point synchronized with the intermediate gear stage. be able to. Therefore, it is possible to suppress the occurrence of shift shock when the third friction element is engaged and perform a smooth shift operation.

  The control apparatus for an automatic transmission according to an eighth aspect of the invention further includes an input shaft rotational speed detection means for detecting the input shaft rotational speed of the speed change mechanism in addition to the configuration of any one of the first to seventh aspects of the invention. . The second time point is a time point when the difference between the detected input shaft rotation speed and the rotation speed at which the input shaft rotation speed is synchronized with the second gear stage is equal to or less than a set value.

  According to the eighth invention, when the difference between the input shaft rotational speed of the transmission mechanism and the rotational speed at which the input shaft rotational speed of the transmission mechanism is synchronized with the second gear stage is equal to or less than the set value, the fourth friction By engaging the elements, the occurrence of a shift shock when the fourth friction element is engaged can be suppressed, and a smooth shift operation can be performed.

  A control device for an automatic transmission according to a ninth aspect of the invention includes, in addition to the configuration of any one of the first to fourth aspects of the invention, an output shaft rotational speed detection means for detecting the output shaft rotational speed of the transmission mechanism, and a detection And a time point learning means for learning the first time point based on the output shaft rotation speed.

  According to the ninth aspect, when shifting from the first gear stage to the second gear stage, a shift shock may occur if the third friction element is engaged before synchronizing with the intermediate gear stage. is there. This is because when the third friction element is engaged earlier than the time when the input shaft rotation speed of the transmission mechanism is synchronized with the intermediate gear stage, the input speed of the transmission mechanism is set so that the rotation speed is synchronized with the intermediate gear stage. The shaft rotation speed may be increased. At this time, a negative torque is generated in the speed change mechanism, resulting in a speed change shock. Therefore, the third friction element can be engaged at an appropriate time point by learning by delaying the first time point based on the output shaft rotation speed of the speed change mechanism. Therefore, it is possible to suppress the occurrence of shift shock when the third friction element is engaged and perform a smooth shift operation.

  According to a tenth aspect of the present invention, in addition to the configuration of the ninth aspect of the invention, the time point learning means learns the first time point based on the detected time variation of the output shaft rotation speed. Means for doing so.

  According to the tenth aspect of the present invention, it is possible to determine whether or not a shift shock due to early engagement of the third friction element has occurred by detecting the amount of time change in the output shaft rotation speed. Thereby, the third friction element can be engaged at an appropriate time by learning by delaying the first time. Therefore, it is possible to suppress the occurrence of shift shock when the third friction element is engaged and perform a smooth shift operation.

It is a schematic block diagram which shows the power train controlled by ECU which is a control apparatus which concerns on embodiment of this invention. It is a skeleton figure which shows the gear train in an automatic transmission. It is a figure which shows the operation | movement table | surface of an automatic transmission. It is a figure which shows a part of hydraulic circuit in an automatic transmission. FIG. 6 is a timing chart when the clutch element switching and the brake element switching are executed stepwise during a shift from the fifth gear to the second gear. It is a functional block diagram of ECU which is a control device of an automatic transmission concerning this embodiment. It is a flowchart which shows the control structure of the program performed with ECU which is a control apparatus of the automatic transmission which concerns on this Embodiment. It is a timing chart which shows operation | movement of ECU which is a control apparatus of the automatic transmission which concerns on this Embodiment. It is a figure for demonstrating the shift shock which arises when the engagement timing of a clutch element is early. It is a figure which shows the relationship between the rotational speed difference of the input / output shaft rotational speed of a torque converter, and the turbine rotational speed at the time of engagement, and a 4-speed synchronous rotational speed. It is a flowchart of the program which learns setting time Ts (1) performed by ECU which is a control apparatus of the automatic transmission which concerns on this Embodiment. It is a figure for demonstrating the shift shock which arises when the engagement timing of a clutch element is early. It is a timing chart which shows change of ΔNO at the time of occurrence of shift shock. It is a flowchart of the program which learns the setting value Ns performed with ECU which is a control apparatus of the automatic transmission which concerns on this Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

<First Embodiment>
A vehicle equipped with a control device according to an embodiment of the present invention will be described with reference to FIG. This vehicle is an FF (Front engine Front drive) vehicle. A vehicle other than FF may be used.

  The vehicle includes an engine 1000, an automatic transmission 2000, a planetary gear unit 3000 that forms part of the automatic transmission 2000, a hydraulic circuit 4000 that forms part of the automatic transmission 2000, a differential gear 5000, a drive shaft 6000, Front wheel 7000 and ECU (Electronic Control Unit) 8000 are included. The control apparatus for an automatic transmission according to the present invention is realized by ECU 8000.

  Engine 1000 is 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, and the crankshaft is rotated.

  Automatic transmission 2000 is connected to engine 1000 via torque converter 3200. Automatic transmission 2000 changes the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear stage.

  The output gear of automatic transmission 2000 is meshed with differential gear 5000. A drive shaft 6000 is connected to the differential gear 5000 by spline fitting or the like. Power is transmitted to the left and right front wheels 7000 via the drive shaft 6000.

  The ECU 8000 includes a vehicle speed sensor 8002, a position switch 8006 of a shift lever 8004, an accelerator opening sensor 8010 of an accelerator pedal 8008, a stroke sensor 8014 of a brake pedal 8012, a throttle opening sensor 8018 of an electronic throttle valve 8016, An engine speed sensor 8020, an input shaft speed sensor 8022, and an output shaft speed sensor 8024 are connected via a harness or the like.

  Vehicle speed sensor 8002 detects the speed of the vehicle from the rotational speed of drive shaft 6000 and transmits a signal representing the detection result to ECU 8000. The position of shift lever 8004 is detected by position switch 8006, and a signal representing the detection result is transmitted to ECU 8000. Corresponding to the position of the shift lever 8004, the gear stage of the automatic transmission 2000 is automatically formed. Further, a manual shift mode in which the driver can select an arbitrary gear stage may be selected according to the driver's operation.

  Accelerator opening sensor 8010 detects the opening of accelerator pedal 8008 and transmits a signal representing the detection result to ECU 8000. Stroke sensor 8014 detects the stroke amount of brake pedal 8012 and transmits a signal representing the detection result to ECU 8000.

  The throttle opening sensor 8018 detects the opening of the electronic throttle valve 8016 whose opening is adjusted by the actuator, and transmits a signal indicating the detection result to the ECU 8000. Electronic throttle valve 8016 adjusts the amount of air taken into engine 1000 (output of engine 1000).

  Engine rotation speed sensor 8020 detects the rotation speed of the output shaft (crankshaft) of engine 1000 and transmits a signal representing the detection result to ECU 8000. Input shaft rotational speed sensor 8022 detects input shaft rotational speed (hereinafter also referred to as turbine rotational speed) NT of automatic transmission 2000, and transmits a signal representing the detection result to ECU 8000. Output shaft rotational speed sensor 8024 detects output shaft rotational speed NO of automatic transmission 2000 and transmits a signal representing the detection result to ECU 8000. Since the output shaft of engine 1000 is connected to the input shaft of torque converter 3200 and the output shaft of torque converter 3200 is connected to the input shaft of automatic transmission 2000, the rotational speed of the output shaft of engine 1000 is the torque. The rotational speed is the same as the rotational speed of the input shaft of converter 3200. Further, the input shaft rotation speed of automatic transmission 2000 is the same as the rotation speed of the output shaft of torque converter 3200.

  ECU 8000 is sent from vehicle speed sensor 8002, position switch 8006, accelerator opening sensor 8010, stroke sensor 8014, throttle opening sensor 8018, engine speed sensor 8020, input shaft speed sensor 8022, output shaft speed sensor 8024, and the like. Based on the received signal, a map and a program stored in a ROM (Read Only Memory), the devices are controlled so that the vehicle is in a desired running state.

  In the present embodiment, ECU 8000 has a 1st to 6th gear stage when D (drive) range is selected as the shift range of automatic transmission 2000 when shift lever 8004 is located at the D (drive) position. Automatic transmission 2000 is controlled so that one of these gears is formed. The automatic transmission 2000 can transmit the driving force to the front wheels 7000 by forming any one of the first to sixth gears.

  When the shift lever 8004 is in the N (neutral) position, when the N (neutral) range is selected as the shift range of the automatic transmission 2000, the automatic transmission 2000 is controlled so as to be in the neutral state (power transmission cut-off state). Is done.

  With reference to FIG. 2, planetary gear unit 3000 provided in automatic transmission 2000 will be described. Planetary gear unit 3000 is connected to a torque converter 3200 having an input shaft 3100 coupled to a crankshaft. Planetary gear unit 3000 includes first set 3300 of planetary gear mechanisms, second set 3400 of planetary gear mechanisms, output gear 3500, B1 brake 3610, B2 brake 3620 and B3 brake 3630 fixed to gear case 3600, and C1. Clutch 3640 and C2 clutch 3650, and one-way clutch F3660 are included.

  The first set 3300 is a single pinion type planetary gear mechanism. First set 3300 includes sun gear S (UD) 3310, pinion gear 3320, ring gear R (UD) 3330, and carrier C (UD) 3340.

  Sun gear S (UD) 3310 is coupled to output shaft 3210 of torque converter 3200. Pinion gear 3320 is rotatably supported by carrier C (UD) 3340. Pinion gear 3320 is in mesh with sun gear S (UD) 3310 and ring gear R (UD) 3330.

  Ring gear R (UD) 3330 is fixed to gear case 3600 by B3 brake 3630. Carrier C (UD) 3340 is fixed to gear case 3600 by B1 brake 3610.

  The second set 3400 is a Ravigneaux type planetary gear mechanism. The second set 3400 includes a sun gear S (D) 3410, a short pinion gear 3420, a carrier C (1) 3422, a long pinion gear 3430, a carrier C (2) 3432, a sun gear S (S) 3440, and a ring gear R. (1) (R (2)) 3450.

  Sun gear S (D) 3410 is coupled to carrier C (UD) 3340. Short pinion gear 3420 is rotatably supported by carrier C (1) 3422. Short pinion gear 3420 is in mesh with sun gear S (D) 3410 and long pinion gear 3430. Carrier C (1) 3422 is coupled to output gear 3500.

  Long pinion gear 3430 is rotatably supported by carrier C (2) 3432. Long pinion gear 3430 is in mesh with short pinion gear 3420, sun gear S (S) 3440, and ring gear R (1) (R (2)) 3450. Carrier C (2) 3432 is coupled to output gear 3500.

  Sun gear S (S) 3440 is coupled to output shaft 3210 of torque converter 3200 by C1 clutch 3640. Ring gear R (1) (R (2)) 3450 is fixed to gear case 3600 by B2 brake 3620 and connected to output shaft 3210 of torque converter 3200 by C2 clutch 3650. The ring gear R (1) (R (2)) 3450 is connected to the one-way clutch F3660 and cannot rotate when the first gear is driven.

  The one-way clutch F3660 is provided in parallel with the B2 brake 3620. That is, the outer race of the one-way clutch F3660 is fixed to the gear case 3600, and the inner race is connected to the ring gear R (1) (R (2)) 3450 via the rotation shaft.

  FIG. 3 shows an operation table showing the relationship between each gear stage and the operation state of each clutch element and each brake element. By operating each brake element and each clutch element in the combinations shown in this operation table, a forward gear stage of 1st to 6th speed and a reverse gear stage are formed.

  As shown in FIG. 3, the C1 clutch 3640 is engaged in all the gears from the first gear to the fourth gear. That is, it can be said that the C1 clutch 3640 is an input clutch in the first gear to the fourth gear. C2 clutch 3650 is engaged at the fifth speed and the sixth speed. That is, it can be said that C2 clutch 3650 is an input clutch at the fifth speed and the sixth speed.

  In the present embodiment, the case where the present invention is applied to an automatic transmission having two input clutches will be described. However, the present invention is not particularly limited as long as it is an automatic transmission having two or more input clutches. Absent.

  The main part of the hydraulic circuit 4000 will be described with reference to FIG. The hydraulic circuit 4000 is not limited to the one described below.

  The hydraulic circuit 4000 includes an oil pump 4004, a primary regulator valve 4006, a manual valve 4100, a solenoid modulator valve 4200, an SL1 linear solenoid (hereinafter referred to as SL (1)) 4210, and an SL2 linear solenoid (hereinafter referred to as “the solenoid valve”). 4220, SL3 linear solenoid (hereinafter referred to as SL (3)) 4230, SL4 linear solenoid (hereinafter referred to as SL (4)) 4240, and SLT linear solenoid (hereinafter referred to as SL (2)). , SLT) 4300, B2 control valve 4500, sequence valve 4600, clutch apply control valve 4700, and B1 apply control valve 4800.

  Oil pump 4004 is connected to the crankshaft of engine 1000. As the crankshaft rotates, the oil pump 4004 is driven to generate hydraulic pressure. The hydraulic pressure generated by the oil pump 4004 is regulated by the primary regulator valve 4006 to generate a line pressure.

  Primary regulator valve 4006 operates using the throttle pressure regulated by SLT 4300 as a pilot pressure. Line pressure is supplied to manual valve 4100 and SL (4) 4240 via line pressure oil passage 4010.

  Manual valve 4100 includes a drain port 4105. From the drain port 4105, the oil pressure in the D range pressure oil passage 4102 and the R range pressure oil passage 4104 is discharged. When the spool of the manual valve 4100 is in the D position, the line pressure oil passage 4010 and the D range pressure oil passage 4102 are communicated, and hydraulic pressure is supplied to the D range pressure oil passage 4102. At this time, the R range pressure oil passage 4104 and the drain port 4105 are communicated, and the R range pressure of the R range pressure oil passage 4104 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the R position, the line pressure oil passage 4010 and the R range pressure oil passage 4104 are communicated, and the oil pressure is supplied to the R range pressure oil passage 4104. At this time, the D-range pressure oil passage 4102 and the drain port 4105 are communicated, and the hydraulic oil in the D-range pressure oil passage 4102 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the N position, both the D range pressure oil passage 4102 and the R range pressure oil passage 4104 are connected to the drain port 4105, and the D range pressure and R of the D range pressure oil passage 4102 are communicated. The hydraulic oil in the range pressure oil passage 4104 is discharged from the drain port 4105.

  The hydraulic pressure (hereinafter also referred to as D range pressure) supplied to the D range pressure oil passage 4102 is transmitted through the clutch apply control valve via the SL (1) 4210, SL (2) 4220, SL (3) 4230 and the oil passage 4106. 4700. The D range pressure is finally supplied to the B1 brake 3610, the B2 brake 3620, the C1 clutch 3640, and the C2 clutch 3650. The R range pressure is finally supplied to the B2 brake 3620.

  The solenoid modulator valve 4200 adjusts the hydraulic pressure (solenoid modulator pressure) supplied to the SLT 4300 to a constant pressure using the line pressure as the original pressure.

  The SLT 4300 adjusts the solenoid modulator pressure in accordance with a control signal from the ECU 8000 based on the accelerator opening detected by the accelerator opening sensor 8010, and generates a throttle pressure. The throttle pressure is supplied to the primary regulator valve 4006 via the SLT oil passage 4302. The throttle pressure is used as a pilot pressure for the primary regulator valve 4006.

  The B2 control valve 4500 selectively supplies the hydraulic pressure from one of the D range pressure oil passage 4102 and the R range pressure oil passage 4104 to the B2 brake 3620. A D range pressure oil passage 4102 and an R range pressure oil passage 4104 are connected to the B2 control valve 4500. The B2 control valve 4500 is controlled by the hydraulic pressure supplied from the SL solenoid valve (not shown) and the SLU solenoid valve (not shown) and the biasing force of the spring.

  When the SL solenoid valve is off and the SLU solenoid valve is on, the B2 control valve 4500 is in the state on the left side in FIG. In this case, the B2 brake 3620 is supplied with the hydraulic pressure adjusted from the D range pressure using the hydraulic pressure supplied from the SLU solenoid valve as a pilot pressure.

  When the SL solenoid valve is on and the SLU solenoid valve is off, the B2 control valve 4500 is in the state on the right side in FIG. In this case, the R range pressure is supplied to the B2 brake 3620.

  SL (1) 4210 regulates the hydraulic pressure supplied to the C1 clutch 3640 via the sequence valve 4600. SL (2) 4220 regulates the hydraulic pressure supplied to C2 clutch 3650 via sequence valve 4600. SL (3) 4230 regulates the hydraulic pressure supplied to the B1 brake 3610 via the B1 apply control valve 4800. SL (4) 4240 regulates the hydraulic pressure supplied to B3 brake 3630 via sequence valve 4600 and clutch apply control valve 4700.

  SL (1) 4210, SL (2) 4220, SL (3) 4230, SL (4) 4240, and SLT 4300 are controlled by a control signal transmitted from ECU 8000.

  SL (1) 4210 and sequence valve 4600 are connected by an oil passage 4212. SL (2) 4220 and sequence valve 4600 are connected by an oil passage 4222. SL (4) 4240 and sequence valve 4600 are connected by an oil passage 4242. Connected by.

  The sequence valve 4600 is controlled by the hydraulic pressure supplied from the SLT 4300 and the solenoid modulator valve 4200 and the biasing force of the spring.

  Note that the sequence valve 4600 is in the right state in FIG. 4 when the spool of the manual valve 4100 is in the D position and is in a normal state. At this time, the oil passage 4212 and the oil passage 4602 connected to the C1 clutch 3640 are communicated, the oil passage 4222 and the oil passage 4604 connected to the C2 clutch 3650 are communicated, and further, the oil passage 4242 and the clutch An oil passage 4606 connected to the apply control valve 4700 is communicated. Oil path 4602, oil path 4604, and oil path 4606 are connected to clutch apply control valve 4700, respectively.

  The clutch apply control valve 4700 is in the state on the right side in FIG. 4 at a speed other than the fourth speed. Specifically, the clutch apply control valve 4700 passes through the oil pressure supplied from the oil passage 4602 to the upper portion of the spool, the oil pressure supplied from the oil passage 4604 to the upper portion of the spool, the oil passage 4012 and the B1 apply control valve 4800. Then, it is controlled by the line pressure supplied from the oil passage 4804 to the lower portion of the spool and the biasing force of the spring.

  In the fourth speed, the hydraulic pressure adjusted by SL (1) 4210 and SL (2) 4220 is supplied to C1 clutch 3640 and C2 clutch 3650 so that C1 clutch 3640 and C2 clutch 3650 are engaged. At this time, in the clutch apply control valve 4700, the force that pushes down the spool based on the hydraulic pressure supplied from the oil passage 4602 and the oil passage 4604 to the spool upper side is the resultant force based on the line pressure supplied to the spool lower side and the biasing force of the spring If it exceeds, it will be in the state of the left side of FIG.

  At this time, the oil passage 4106 and the oil passage 4704 connected to the upper part of the spool of the B1 apply control valve 4800 are communicated. Therefore, the D range pressure is supplied to the upper portion of the spool of the B1 apply control valve 4800 via the oil passage 4106 and the oil passage 4704.

  On the other hand, at the speeds other than the fourth speed, the hydraulic pressure adjusted by SL (1) 4210 and SL (2) 4220 is set so that either one of C1 clutch 3640 and C2 clutch 3650 is engaged. Supplied to one of the clutches 3650. At this time, in clutch apply control valve 4700, the force of pushing down the spool based on the oil pressure supplied from the oil passage 4602 and oil passage 4604 to the upper portion of the spool is lower than the resultant force based on the line pressure supplied to the lower portion of the spool and the biasing force of the spring. Therefore, the state on the right side of FIG. 4 is obtained. Therefore, the oil passage 4606 and the oil passage 4702 connected to the B3 brake 3630 are communicated.

  The B1 apply control valve 4800 is branched and connected from the oil passage 4010 to the oil pressure supplied from the oil passage 4704 to the upper portion of the spool, the oil pressure supplied from the oil passage 4702 connected to the B3 brake 3630 to the upper portion of the spool. The oil pressure is supplied from the oil passage 4012 to the lower portion of the spool, the oil pressure supplied from the oil passage 4232 to the upper portion of the spool, and the biasing force of the spring.

  When hydraulic pressure is supplied to the oil passage 4702 connected to the B3 brake 3630, the force that pushes down the spool based on the hydraulic pressure supplied to the upper side of the spool generates the resultant force based on the hydraulic pressure supplied to the lower portion of the spool and the biasing force of the spring. Therefore, the B1 apply control valve 4800 is in the state on the right side in FIG.

  On the other hand, when the hydraulic pressure supplied to the oil passage 4702 connected to the B3 brake 3630 decreases, the force for pushing down the spool based on the hydraulic pressure supplied to the upper side of the spool is based on the hydraulic pressure supplied to the lower portion of the spool and the biasing force of the spring. Since it is less than the resultant force, the B1 apply control valve 4800 is in the state on the left side in FIG.

  SL (3) 4230 is connected to B1 apply control valve 4800 with oil passage 4232 interposed. In addition, an oil passage 4234 branched in the middle of the oil passage 4232 is further connected to the B1 apply control valve 4800. When the B1 apply control valve 4800 is in the left side in FIG. 4, the oil passage 4234 and the oil passage 4802 connected to the B1 brake 3610 are brought into communication.

  In the configuration of the vehicle as described above, for example, the shift from the fifth gear to the second gear is changed from the C1 clutch 3640 to the C2 clutch 3650 via the intermediate gear (third gear), and the B3 brake 3630 is shifted. A case where the changeover from B1 to B1 brake 3610 is performed in stages will be described with reference to FIG.

  In the hydraulic circuit 4000, when the fifth speed is established, the hydraulic pressure is supplied from the SL (2) 4220 to the C2 clutch 3650 via the sequence valve 4600, and the sequence valve 4600 and the clutch apply control valve are transmitted from the SL (4) 4240. In this state, the hydraulic pressure is supplied to the B3 brake 3630 via 4700.

  At this time, the clutch apply control valve 4700 is in the state on the right side in FIG. On the other hand, the B1 apply control valve 4800 is in the state on the right side in FIG.

  When shifting from the fifth speed to the second speed, the C2 clutch 3650 is first released and then the C1 clutch 3640 is engaged, so that the C2 clutch 3650 and the C1 clutch 3640 are switched. It is done. In this way, a shift from the fifth speed to the third speed, which is an intermediate speed, is performed. Further, the B3 brake 3630 is released and the B1 brake 3610 is engaged, whereby the B3 brake 3630 and the B1 brake 3610 are switched. In this way, a shift from the third speed to the second speed is performed.

  More specifically, when the shift from the fifth gear to the second gear is started based on the gear shift command output from ECU 8000 to hydraulic circuit 4000, the command pressure of SL (4) 4240 increases. Therefore, as shown in FIG. 5A, at time Ta (0), the control pressure of the B3 brake 3630 (also referred to as engagement pressure in the following description) increases. On the other hand, since the command pressure of SL (2) 4220 decreases, the control pressure of C2 clutch 3650 decreases at time Ta (1) as shown in FIG. 5B.

  As the control pressure of the C2 clutch 3650 decreases and the command pressure of the SL (1) 4210 increases, the control pressure of the C1 clutch 3640 increases at time Ta (2) as shown in FIG. 5C. . At this time, in the automatic transmission 2000, the control pressure of the C1 clutch 3640 increases, the control pressure of the C2 clutch 3650 decreases, and since the B3 brake 3630 is engaged, formation of the third gear is started. The

  At time Ta (3), the control pressure of the B3 brake 3630 decreases due to the decrease in the command pressure of SL (4) 4240 as shown in FIG. 5 (A). Further, as the indicated pressure of SL (1) 4210 is further increased, the control pressure of C1 clutch 3640 is increased as shown in FIG.

  At the time Ta (4), the third speed stage is formed, and as shown in FIG. 5 (E), the engine speed NE and the turbine speed NT are lowered to the speed corresponding to the third speed stage and are stagnant. To do.

  At time Ta (5), the control pressure of the B3 brake 3630 decreases as shown in FIG. 5 (A) due to a further decrease in the command pressure of SL (4) 4240. At the same time, the control pressure of the C1 clutch 3640 increases as shown in FIG. 5C due to a further increase in the indicated pressure of the SL (1) 4210.

  At time Ta (6), the control pressure of the B1 brake 3610 increases as shown in FIG. 5 (D) due to the increase of the command pressure of SL (3) 4230. That is, the shift from the third gear to the second gear is started.

  As the control pressure of the C1 clutch 3640 and the B1 brake 3610 increases and the control pressure of the B3 brake 3630 decreases, as shown in FIG. 5 (E), the engine speed NE and the turbine speed NT become the second gear. It will rise until it becomes the rotation speed corresponding to, and will be in the state where it stagnated at the rotation speed corresponding to the 2nd gear stage after that. That is, the shift is completed at time Ta (7).

  As described above, when the third speed is formed as an intermediate gear at the time of shifting from the fifth speed to the second speed, the engine speed NE and the turbine speed NT are set at the speed synchronized with the intermediate gear. After stagnating, according to the formation of the second speed stage, the engine speed increases to the rotational speed synchronized with the second speed stage.

  Therefore, when changing gears such as changing the C1 clutch 3640 and the C2 clutch 3650 and changing the B3 brake 3630 and the B1 brake 3610 in stages, the responsiveness of the change may deteriorate. . Further, since the gear stage after the shift is formed after the intermediate gear stage is completely formed, it may take a long time from the start of the shift to the completion.

  Further, if the C2 clutch 3650 and the B3 brake 3630 are released at the same time, the rotational state of the rotating elements in the automatic transmission 2000 cannot be grasped, so that a shift shock may occur when the C1 clutch 3640 and the B1 brake 3610 are engaged. .

  Therefore, according to the present invention, the ECU 8000 reduces the engagement force of the first friction element so that the first friction element is released when shifting from the first gear stage to the second gear stage. When the first friction element is released, the engagement force of the second friction element is decreased so as to be a predetermined engagement force. And the engagement of the third friction element further decreases the engagement force of the second friction element so that the second friction element is released, and the second time point is later than the first time point. Thus, the automatic transmission 2000 (more specifically, various solenoids provided in the hydraulic circuit 4000) is controlled to increase the engagement force of the fourth friction element.

  In the present embodiment, the “first gear stage” is the fifth speed stage. The “second gear stage” is the second speed stage. The “first friction element” is the B3 brake 3630. The “second friction element” is the C2 clutch 3650. The “third friction element” is the C1 clutch 3640. The “fourth friction element” is the B1 brake 3610.

  More specifically, ECU 8000 controls SL (4) 4240 so that the control pressure of B3 brake 3630 decreases during a shift from the fifth gear to the second gear. ECU 8000 controls SL (4) 4240 so that B3 brake 3630 is released.

  ECU 8000 controls SL (2) 4220 so that the control pressure of C2 clutch 3650 decreases to a predetermined control pressure when B3 brake 3630 is released.

  ECU 8000 synchronizes the input shaft rotation speed (turbine rotation speed NT) of planetary gear unit 3000, which is a transmission mechanism, with the fourth gear stage formed by engagement of C2 clutch 3650 and C1 clutch 3640 after the start of shifting. SL (1) 4210 is controlled so that the control pressure of the C1 clutch 3640 increases at approximately the same time as when the rotation speed is reached.

  ECU 8000 controls SL (2) 4220 so that the control pressure of C2 clutch 3650 further decreases with the engagement of C1 clutch 3640.

  The ECU 8000 increases the control pressure of the B1 brake 3610 when the difference between the input shaft rotation speed (turbine rotation speed NT) of the planetary gear unit 3000 and the rotation speed synchronized with the second gear is equal to or less than a set value. SL (3) 4230 is controlled.

  The “predetermined control pressure (engagement force)” is the rotation of the planetary gear unit 3000 after the C1 clutch 3640 starts engaging until the engaged state is controlled. The control pressure is not particularly limited as long as it is a control pressure that causes slippage in the C2 clutch 3650 due to torque transmitted through the element.

  Hereinafter, the configuration of ECU 8000 in the present embodiment will be described with reference to the functional block diagram shown in FIG.

  As shown in FIG. 6, the ECU 8000 includes an input interface (hereinafter referred to as an input I / F) 300 that receives signals from various sensors, and an arithmetic processing unit 400 mainly composed of a CPU (Central Processing Unit). , Which is realized by the above-described ROM or the like, and transmits a control command based on a result calculated in the arithmetic processing unit 400, and a storage unit 600 that stores various information such as threshold values and maps, and various programs, to the hydraulic circuit 4000. An output interface (hereinafter referred to as an output I / F) 500 is provided.

  In the present embodiment, the input I / F 300 includes an engine speed signal, a vehicle speed signal, a shift position signal, an accelerator position signal, a throttle position signal, an input shaft speed signal, and an output shaft speed. Signal.

  The arithmetic processing unit 400 includes a shift execution determination unit 402, a release control unit (1) 404, a semi-engagement control unit 406, an engagement control unit (1) 408, a release control unit (2) 410, A combined control unit (2) 412 and a shift determination unit 414 are included.

  A shift execution determination unit 402 determines whether or not to execute a direct shift from the fifth speed to the second speed. “Direct shift” refers to shifting directly over a plurality of stages such as the sixth speed to the third speed or the fifth speed to the second speed without completely forming the intermediate gear. The shift execution determination unit 402, for example, in the shift diagram stored in the storage unit 600 based on the detected accelerator opening, the vehicle speed, and the current gear position based on the ratio of the input shaft rotation speed and the output shaft rotation speed. When a plurality of downshift lines from 5th to 4th gear, 4 to 3rd gear and 3 to 2nd gear are crossed continuously, it is determined that a direct shift from 5th gear to 2nd gear is executed. . Note that the shift execution determination unit 402 turns on the direct shift execution flag when it is determined to execute a direct shift from the fifth gear to the second gear, for example.

  The release control unit (1) 404 generates a control command signal so that the B3 brake 3630 is released when a shift from the fifth gear to the second gear is executed, and passes through the output I / F 500. To the hydraulic circuit 4000. For example, when the direct shift execution flag from the 5th speed to the 2nd speed is turned on, or when a predetermined time elapses after the release control section (1) 404 is turned on, A control command signal is generated so as to reduce the control pressure.

  The half-engagement control unit 406 generates a control command signal so that the control pressure of the C2 clutch 3650 becomes a predetermined control pressure along with the release of the B3 brake 3630, and via the output I / F 500, Transmit to hydraulic circuit 4000. For example, when the direct shift execution flag from the 5th speed to the 2nd speed is turned on, or when a predetermined time elapses after being turned on, the half-engagement control unit (1) 406 receives the C2 clutch. A control command signal is generated so that the control pressure of 3650 becomes a predetermined control pressure.

  The engagement control unit (1) 408 is configured so that the input shaft rotational speed of the planetary gear unit 3000 is synchronized with the fourth speed formed by the engagement of the C2 clutch 3650 and the C1 clutch 3640 after the shift is started. At substantially the same time as this, a control command signal is generated so that the control pressure of the C1 clutch 3640 increases, and is transmitted to the hydraulic circuit 4000 via the output I / F 500.

  In the present embodiment, the engagement control unit (1) 408 generates a control command signal so that the control pressure of the C1 clutch 3640 increases after the set time has elapsed since the control command signal for the B3 brake 3630 is transmitted. Is done. The set time is a time set so as to correspond to a point in time when the input shaft rotational speed of the planetary gear unit 3000 becomes a rotational speed synchronized with the fourth gear after the command value for the B3 brake 3630 is transmitted. The set time is measured by the time measuring unit 416.

  The release control unit (2) 410 generates a control command signal so that the control pressure of the C2 clutch 3650 is further lowered while the C1 clutch 3640 is engaged, and the hydraulic pressure is output via the output I / F 500. Transmit to circuit 4000.

  In the present embodiment, the release control unit (2) 410 receives the control pressure of the C2 clutch 3650 after a predetermined time has elapsed after the engagement control unit (1) 408 transmits the control command signal. A control command signal is generated so as to further decrease. The predetermined time is measured by the time measuring unit 416.

  The engagement control unit (2) 412 controls the control pressure so that the control pressure of the B1 brake 3610 increases at approximately the same time as when the input shaft rotation speed of the planetary gear unit 3000 reaches the rotation speed synchronized with the second gear. A signal is generated and transmitted to the hydraulic circuit 4000 via the output I / F 500.

  In the present embodiment, the engagement control unit (2) 412 is configured so that when the difference between the input shaft rotational speed of the planetary gear unit 3000 and the rotational speed synchronized with the second gear is less than or equal to a set value, A control command signal is generated so that the control pressure increases.

  The shift determination unit 414 determines that the shift has been completed when the ratio between the turbine rotational speed NT and the output shaft rotational speed NO is substantially the same as the speed ratio corresponding to the speed stage after the speed change (second speed stage). To do. When the shift determination unit 414 determines that the shift has been completed, the gear engagement determination flag is turned on.

  The time measurement unit 416 is a timer that measures the elapsed time by setting the count value to the initial value when the elapsed time measurement is started and adding a predetermined count value for each calculation cycle. is there.

  In this embodiment, the shift execution determination unit 402, the release control unit (1) 404, the half-engagement control unit 406, the engagement control unit (1) 408, the release control unit (2) 410, the engagement control unit (2) 412, the shift determination unit 414, and the time measurement unit 416 all function as software realized by the CPU that is the arithmetic processing unit 400 executing the program stored in the storage unit 600. Although described, it may be realized by hardware. Such a program is recorded on a recording medium and mounted on the vehicle.

  Hereinafter, with reference to FIG. 7, a control structure of a program executed by ECU 8000 which is the control device for the automatic transmission according to the present embodiment will be described.

  In step (hereinafter step is referred to as S) 100, ECU 8000 determines whether or not a direct shift is started. When the direct shift is started (YES in S100), the process proceeds to S102. If not (NO in S100), the process waits until the direct shift is started.

  In S102, ECU 8000 starts monitoring changes in turbine speed NT and output shaft speed NO. ECU 8000 may constantly monitor changes in turbine speed NT and output shaft speed NO.

  In S104, ECU 8000 starts hydraulic control. In S106, ECU 8000 controls hydraulic circuit 4000 so that release element (1) is completely released. In the present embodiment, the “release element (1)” is the B3 brake 3630. That is, ECU 8000 controls SL (4) 4240 so that the control pressure of B3 brake 3630 decreases.

  In S108, ECU 8000 starts timer (1) and starts time measurement. In S110, ECU 8000 controls hydraulic circuit 4000 so that the control pressure of release element (2) is reduced to a predetermined control pressure. In the present embodiment, the “release element (2)” is the C2 clutch 3650. That is, ECU 8000 controls SL (2) 4220 so that the control pressure of C2 clutch 3650 is reduced to a predetermined control pressure.

  In S112, ECU 8000 determines whether or not the count value of timer (1) is equal to or greater than the value corresponding to set time Ts (1). If the count value is equal to or greater than the value corresponding to set time Ts (1) (YES in S112), the process proceeds to S114. If not (NO in S112), the process waits until the count value becomes equal to or greater than the value corresponding to set time Ts (1).

  In S114, ECU 8000 controls hydraulic circuit 4000 so that the control pressure of engagement element (1) increases. In the present embodiment, the “engagement element (1)” is the C1 clutch 3640. That is, ECU 8000 controls SL (1) 4210 so that the control pressure of C1 clutch 3640 increases.

  In S116, ECU 8000 starts timer (2) and starts time measurement. In S118, ECU 8000 determines whether or not the count value of timer (2) is equal to or greater than the value corresponding to set time Ts (2). If the count value is equal to or greater than the value corresponding to set time Ts (2) (YES in S118), the process proceeds to S120. If not (NO in S118), the process waits until the count value becomes equal to or greater than the value corresponding to set time Ts (2).

  In S120, ECU 8000 controls hydraulic circuit 4000 so that release element (2) (C2 clutch 3650) is completely released.

  In S122, ECU 8000 determines whether or not turbine rotational speed NT is equal to or greater than (gear stage synchronous rotational speed after shift-setting value Ns). If turbine rotational speed NT is equal to or greater than (gear-stage synchronous rotational speed after shift-setting value Ns) (YES in S122), the process proceeds to S124. If not (NO in S122), the system waits until turbine rotational speed NT becomes equal to or greater than (gear-stage synchronous rotational speed after shift-setting value Ns).

  In S124, ECU 8000 controls hydraulic circuit 4000 so that the control pressure of engagement element (2) increases. In the present embodiment, the “engaging element (2)” is the B1 brake 3610. That is, ECU 8000 controls SL (3) 4230 so that the control pressure of B1 brake 3610 increases.

  In S126, ECU 8000 determines whether or not the gear engagement determination flag after the shift is on. If the gear engagement determination flag after the shift is on (YES in S126), the process proceeds to S128. If not (NO in S126), the process waits until the gear engagement determination flag after shifting is turned on.

  The operation of ECU 8000 serving as the automatic transmission control apparatus according to the present embodiment based on the above-described structure and flowchart will be described with reference to FIG. 8 as an example of direct shift from the fifth speed to the second speed.

  For example, assume that automatic transmission 2000 has a fifth gear. At this time, the C2 clutch 3650 and the B3 brake 3630 are engaged.

  When the accelerator pedal 8008 is depressed by the driver, the slot opening increases. As a result, the engine speed NE increases. As the engine speed NE increases, the engine torque output from the engine 1000 increases. Then, the output shaft torque of automatic transmission 2000 increases.

  When the driver depresses the accelerator, the relationship between the vehicle speed and the accelerator opening in the shift map changes. When the position on the shift diagram specified by the vehicle speed and the accelerator opening crosses each downshift line from 5th to 4th speed, 4th to 3rd speed and 3rd to 2nd speed continuously, ECU 8000 It is determined that the direct shift is started (YES in S100). At this time, monitoring of the turbine speed NT and the output shaft speed NO is started (S102), and hydraulic pressure control is started (S104).

  When the hydraulic control is started, the release control is started so that the B3 brake 3630 is completely released (S106). When the release control is started, as shown in FIG. 8A, the control pressure of the B3 brake 3630 once increases at time Tb (0), and then starts decreasing at time Tb (1).

  When the release control of the B3 brake 3630 is started, the timer (1) is started (S108). Then, half-engagement control is started so that the control pressure of the C2 clutch 3650 is reduced to a predetermined control pressure (S110). When the pressure is lowered to a predetermined control pressure, as shown in FIG. 8B, the control pressure of the C2 clutch 3650 once increases at time Tb (0) and then decreases at time Tb (1). At a time Tb (3), a predetermined control pressure is maintained.

  Since the B3 brake 3630 is released and the C2 clutch 3650 is in a half-engaged state, the degree of transmission of the engine torque of the engine 1000 to the output shaft side is reduced. Therefore, as shown in FIG. 8 (G), the output shaft torque decreases after time Tb (1). As shown in FIG. 8E, the engine speed NE increases because the rotational load on the engine 1000 by the automatic transmission 2000 decreases.

  When the count value of timer (1) becomes equal to or greater than the value corresponding to set time Ts (1) (YES in S112), as shown in FIG. 8 (C), control of C1 clutch 3640 is performed at time Tb (2). Engagement control is started so that the pressure increases (S114).

  At this time, as shown in FIG. 8 (F), the control pressure of the C1 clutch 3640 further increases when the differential rotational speed between the turbine rotational speed NT and the synchronous rotational speed of the fourth gear is substantially zero. Since the C1 clutch 3640 is engaged when the differential rotation speed between the turbine rotation speed and the synchronous rotation speed of the fourth gear is substantially zero, the shift shock when the C1 clutch 3640 is engaged is suppressed.

  Engagement control of the C1 clutch 3640 is started and the timer (2) is started (S116). When the count value of timer (2) becomes equal to or greater than the value corresponding to set time Ts (2) (YES in S118), release control is started so that C2 clutch 3650 is completely released (S120). When the release control is started, as shown in FIG. 8B, the C2 clutch 3650 is substantially completely released at time Tb (5).

  When turbine rotational speed NT is equal to or greater than (second-speed synchronous rotational speed−set value Ns) (YES in S122), engagement control is started so that the control pressure of B1 brake 3610 increases (S124). ). When the engagement control of the B1 brake 3610 is started, as shown in FIG. 8D, the control pressure of the B1 brake 3610 increases after time Tb (4).

  If it is determined at time Tb (6) that the ratio between the turbine speed NT and the output shaft speed NO is substantially the same as the gear ratio of the second gear, the second gear stage engagement determination flag Is turned on (YES in S126), the hydraulic control is terminated (S128).

  As described above, according to the control device for the automatic transmission according to the present embodiment, the engaging force of both the B3 brake and the C2 clutch is controlled simultaneously, and the C1 clutch is engaged when synchronized with the fourth gear. By engaging the B1 brake at the time of synchronization with the second gear, the intermediate gear is completely compared with the case where the switching between the C2 clutch and the C1 clutch and the switching between the B3 brake and the B1 brake are performed stepwise. Therefore, the speed change operation can be completed in a short time.

  Further, since it is not necessary to completely form the intermediate gear stage, the change in the engine speed does not stagnate during the shift. Therefore, it is possible to improve the response of shifting.

  Further, by engaging the C1 clutch at the time point synchronized with the fourth speed, it is possible to suppress a shift shock when the C1 clutch is engaged. Further, by engaging the B1 brake at the time of synchronization with the second gear, it is possible to suppress a shift shock when the B1 brake is engaged. Therefore, it is possible to provide a control device for an automatic transmission that improves the responsiveness of shift and prevents shift shock.

  In this embodiment, the shift operation will be described by taking the direct shift from the fifth speed to the second speed as an example. However, it is necessary to switch between the clutch element (input element) and the brake element (reaction force element). If it is a gear shift, it will not be limited to this in particular.

  For example, at the sixth speed, C2 clutch 3650 and B1 brake 3610 are engaged. In the case of direct shifting from the sixth gear to the third gear, the C2 clutch 3650 is switched to the C1 clutch 3640, and the B1 brake 3610 is switched to the B3 brake 3630.

  That is, at the time of shifting from the sixth speed to the third speed, the release control is performed so that the B1 brake 3610 is completely released, and the C2 clutch 3650 is controlled to be half-engaged so as to have a predetermined control pressure. The The “predetermined control pressure” is the same as the predetermined control pressure at the time of shifting from the fifth gear to the second gear.

  Engagement control of the C1 clutch 3640 is started at the time point synchronized with the fourth speed. At this time, since the C1 clutch 3640 is engaged and the C2 clutch 3650 is half-engaged, a gear position close to the fourth gear is formed. And B3 brake 3630 is engaged at the time of synchronizing with the third gear. As a result, the shift from the sixth gear to the third gear can be completed in a short time without causing a shift shock.

  Further, in the present embodiment, the set time Ts (1) may be set to a predetermined time, but learning is performed according to the state of the automatic transmission 2000, and the learned time is newly set. You may make it update as time Ts (1).

  This is because if the engagement timing of the C1 clutch 3640 is late (that is, if the set time Ts (1) is large), a positive torque may be generated in the automatic transmission 2000.

  For example, assume a direct shift from the fifth speed to the second speed. As shown in FIGS. 9A and 9B, after the B3 brake 3630 is controlled to be released and the C2 clutch 3650 is controlled to be half-engaged, as shown in FIG. 9C, the time Tc (0 ), The C1 clutch 3640 is engaged. At this time, if the engagement timing of the C1 clutch 3640 is late, the C1 clutch 3640 is engaged beyond the point in time when the turbine rotation speed NT reaches the rotation speed synchronized with the fourth gear. Therefore, turbine rotational speed NT is lowered to a rotational speed synchronized with the fourth gear while C1 clutch 3640 is engaged. As a result, as shown in FIG. 9F, a shift shock on the positive torque side occurs at Tc (1).

  When such a reduction in the rotational speed occurs, as shown in FIG. 9 (E), at time TC (1), the difference between the input shaft rotational speed and the output shaft rotational speed of torque converter 3200 (below, In the description, NSLP) increases and slipping occurs. That is, when the occurrence of slippage is detected in torque converter 3200 after the timing at which C1 clutch 3640 is engaged, it can be determined that the aforementioned reduction in the rotational speed has occurred.

  As shown in FIG. 10, the rotational speed difference between the input side and the output side of the torque converter 3200 is the rotational speed difference between the turbine rotational speed NT when the C1 clutch 3640 is engaged and the rotational speed synchronized with the fourth gear. And has a substantially proportional relationship. Note that the horizontal axis of FIG. 10 indicates the differential rotational speed between the turbine rotational speed NT when the C1 clutch 3640 as an input element is engaged and the rotational speed synchronized with the fourth gear. The vertical axis in FIG. 10 indicates the differential rotational speed between the input shaft rotational speed and the output shaft rotational speed of the torque converter 3200 that is a fluid coupling. As shown in FIG. 10, when the differential rotational speed between the turbine rotational speed NT and the rotational speed synchronized with the fourth gear is large, the differential rotational speed between the input shaft rotational speed and the output shaft rotational speed of the torque converter 3200 is also proportional. Tend to increase.

  Therefore, the set time Ts (1) may be learned based on the input rotation speed and the output shaft rotation speed of the torque converter 3200 that is a fluid coupling.

  Hereinafter, with reference to FIG. 11, a control structure of a program for learning set time Ts (1), which is executed by ECU 8000 which is the control device for the automatic transmission according to the present embodiment, will be described.

  In S200, ECU 8000 determines whether or not power-on downshift control is being performed. “Power-on downshift control” refers to downshift control that crosses the downshift line by changing the relationship between the accelerator opening and the vehicle speed in the shift map as the driver depresses the accelerator pedal. . If power-on downshift control is being performed (YES in S200), the process proceeds to S202. Otherwise (NO in S200), this process ends.

  In S202, ECU 8000 determines whether or not a learning permission condition is satisfied. The “learning permission condition” includes, for example, an oil temperature condition (condition that the oil temperature is equal to or lower than a predetermined temperature), and an input torque condition (input torque (engine speed) that is predetermined) (torque speed). A condition that the vehicle speed is equal to or less than a predetermined vehicle speed), an accelerator opening condition (a condition that the time change amount of the accelerator opening is equal to or less than a predetermined change amount), and This includes a condition that complicated multiple shift control is not executed. The learning permission condition may be a condition in which learning is not performed in a state where the accuracy of learning cannot be guaranteed, and at least the conditions described above may be included. If the learning permission condition is satisfied (YES in S202), the process proceeds to S204. Otherwise (NO in S202), this process ends.

  In S204, ECU 8000 determines whether the NSLP detection condition is satisfied. Here, “NSLP” indicates the slip amount in the torque converter 3200, and is calculated by the difference between the input shaft rotational speed and the output shaft rotational speed of the torque converter 3200. The input shaft speed of torque converter 3200 is detected by engine speed sensor 8020. Further, the output shaft rotational speed of torque converter 3200 is detected by input shaft rotational speed sensor 8022.

  The “NSLP detection condition” is, for example, a condition in which the turbine rotational speed NT is equal to or higher than the rotational speed synchronized with the fourth speed, which is an intermediate gear, at the time of direct shift from the fifth speed to the second speed. It is. If the NSLP detection condition is satisfied (YES in S204), the process proceeds to S206. If not (NO in S204), the process returns to S202.

  In S206, ECU 8000 determines whether NSLP is within a predetermined range. The predetermined range is adapted by, for example, experiments. If NSLP is within a predetermined range (YES in S206), this process ends. If not (NO in S206), the process proceeds to S208.

  In S208, ECU 8000 updates the learning value. Specifically, ECU 8000 shortens set time Ts (1) by a predetermined time, and implements advance engagement timing of C1 clutch 3640. ECU 8000 may store the relationship between set time Ts (1) and NSLP in advance, for example, as a map, table, or mathematical expression.

  An operation in which ECU 8000 serving as the automatic transmission control apparatus according to the present embodiment learns set time Ts (1) based on the flowchart as described above will be described.

  For example, it is assumed that a direct shift from the fifth gear to the second gear is performed by the driver depressing the accelerator pedal. When the shift is started, since it is power-on downshift control (YES in S200), it is determined whether or not a learning permission condition is satisfied (S202).

  The learning permission conditions, that is, the oil temperature condition, the input torque condition, the vehicle speed condition, the accelerator opening condition, and the condition that the complicated multiple shift control is not executed are all satisfied (YES in S202), and the turbine rotational speed NT is When the rotational speed is synchronized with the fourth gear (YES in S204), NSLP is detected.

  That is, the differential rotational speed between the engine rotational speed NE and the turbine rotational speed NT is calculated. At this time, if the detected NSLP is not within a predetermined range (NO in S206), the learning value is updated (S208). That is, the set time Ts (1) is updated so as to be shortened by a predetermined time.

  When the setting time Ts (1) is newly set to be shortened, the engagement timing of the C1 clutch 3640 is advanced. Therefore, since the engagement of the C1 clutch 3640 is performed at an appropriate time, the reduction of the turbine speed NT when the C1 clutch 3640 is engaged is suppressed. Therefore, since generation of positive torque is suppressed, a shift shock when the C1 clutch 3640 is engaged can be suppressed.

  On the other hand, when the engagement timing of the C1 brake 3640 is early (that is, when the set time Ts (1) is small), the turbine rotational speed NT is increased to the rotational speed synchronized with the fourth gear that is the intermediate gear stage. There is a possibility that a negative torque is generated in the automatic transmission 2000.

  As shown in FIG. 12, when the engagement start point of the C1 brake 3640 is earlier than the time when the C1 brake 3640 is synchronized with the intermediate gear (the fourth speed in the present embodiment), the turbine speed NT is synchronized with the fourth speed. In a state where the rotational speed has not been fully increased, the state is close to the fourth speed stage. For this reason, the turbine rotation speed NT is increased to a rotation speed synchronized with the fourth speed stage, so that the rate of change of the increase in the turbine rotation speed NT increases. At this time, since the output shaft torque changes to the negative torque side, a shift shock occurs.

  As shown in FIG. 13, when such a negative torque is generated, the time variation ΔNO of the output shaft rotation speed of automatic transmission 2000 greatly changes. That is, when the time change amount ΔNO of the output shaft rotation speed is large during the shift, it can be determined that the above-described increase in the rotation speed has occurred.

  Therefore, the set time Ts (1) may be learned based on the amount of time change in the output shaft rotation speed of the automatic transmission 2000.

  Hereinafter, with reference to FIG. 14, a control structure of a program for learning set time Ts (1), which is executed by ECU 8000 which is the control device for the automatic transmission according to the present embodiment, will be described.

  In S300, ECU 8000 determines whether or not the power-on downshift control is being performed. If power-on downshift control is being performed (YES in S300), the process proceeds to S302. Otherwise (NO in S300), this process ends.

  In S302, ECU 8000 determines whether or not a learning permission condition is satisfied. The “learning permission condition” is described as being the same condition as the “learning permission condition” described above, but may be different. If the learning permission condition is satisfied (YES in S302), the process proceeds to S304. If not (NO in S302), this process ends.

  In S304, ECU 8000 determines whether or not a detection condition for ΔNO is satisfied. The “ΔNO detection condition” is, for example, the absolute difference between the turbine speed NT and the speed synchronized with the fourth speed, which is the intermediate gear, during direct shift from the fifth speed to the second speed. This is a condition that the value is equal to or less than a predetermined value. If the ΔNO detection condition is satisfied (YES in S304), the process proceeds to S306. If not (NO in S304), the process returns to S302.

  In S306, ECU 8000 determines whether ΔNO is within a predetermined range A or not. ECU 8000 calculates the amount of time change in output shaft rotational speed NO detected by the output shaft rotational speed sensor. The predetermined range A is adapted by, for example, experiments. The predetermined range A is defined from an upper limit value and a lower limit value of ΔNO, for example, as shown in FIG. The ECU 8000 determines that the calculated ΔNO is equal to or smaller than the upper limit value of the predetermined range A and is equal to or larger than the lower limit value. If ΔNO is within predetermined range A (YES in S306), this process ends. If not (NO in S306), the process proceeds to S308.

  In S308, ECU 8000 updates the learning value. Specifically, ECU 8000 increases set time Ts (1) by a predetermined value to delay the engagement timing of C1 brake 3640. ECU 8000 may store the relationship between ΔNO and set time Ts (1) in advance, for example, as a map, table, or mathematical expression.

  An operation in which ECU 8000 serving as the automatic transmission control apparatus according to the present embodiment learns set time Ts (1) based on the flowchart as described above will be described.

  For example, it is assumed that a direct shift from the fifth gear to the second gear is performed by the driver depressing the accelerator pedal. When the shift is started, since it is power-on downshift control (YES in S300), it is determined whether or not a learning permission condition is satisfied (S302).

  The learning conditions such as the oil temperature condition, the input torque condition, the vehicle speed condition, the accelerator opening condition, and the condition that the complex multiple shift control is not executed are all satisfied (YES in S302), and the turbine speed and the fourth speed are satisfied. When the absolute value of the difference from the rotational speed synchronized with the stage is equal to or smaller than a predetermined value (YES in S304), ΔNO is detected. That is, the time change amount of the output shaft rotational speed NO of the automatic transmission 2000 is calculated. At this time, if the calculated ΔNO is not within the predetermined range A (NO in S306), the learning value is updated (S308). That is, the set time Ts (1) is updated so as to increase by a predetermined value.

  When the setting time Ts (1) is newly set so as to increase, the engagement timing of the C1 brake 3640 is delayed. Therefore, since the engagement of the C1 brake 3640 is performed at an appropriate time, the increase in the turbine speed NT when the C1 brake 3640 is engaged is suppressed. Therefore, since the generation of negative torque is suppressed, a shift shock when the C1 brake 3640 is engaged can be suppressed.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1000 engine, 2000 automatic transmission, 3000 planetary gear unit, 3100 input shaft, 3200 torque converter, 3210 output shaft, 3610 B1 brake, 3620 B2 brake, 3630 B3 brake, 3640 C1 clutch, 3650 C2 clutch, 3660 one-way clutch F, 4000 hydraulic Circuit, 4004 Oil pump, 4006 Primary regulator valve, 4100 Manual valve, 4200 Solenoid modulator valve, 4210 SL1 linear solenoid, 4220 SL2 linear solenoid, 4230 SL3 linear solenoid, 4240 SL4 linear solenoid, 4300 SLT linear solenoid, 4500 B2 control valve, 4600 sequence valve, 700 clutch apply control valve, 4800 B1 apply control valve, 8000 ECU, 8002 vehicle speed sensor, 8004 shift lever, 8006 position switch, 8008 accelerator pedal, 8010 accelerator opening sensor, 8012 brake pedal, 8014 stroke sensor, 8016 electronic throttle valve, 8018 throttle opening sensor, 8020 engine speed sensor, 8022 input shaft speed sensor, 8024 output shaft speed sensor.

Claims (15)

A first gear is formed when the first friction element and the second friction element are engaged and the third friction element and the fourth friction element are released, and the first friction element is formed. An automatic transmission in which a second gear is formed when an element and the second friction element are in the released state and the third friction element and the fourth friction element are in the engaged state. A control device,
The control device releases the first friction element and maintains the second friction element in a predetermined state when shifting from the first gear stage to the second gear stage. 3 increase the engagement force of the friction element,
The control apparatus for an automatic transmission, wherein the predetermined state is a state in which slippage occurs in the second friction element when the third friction element is engaged . The automatic transmission is third when the second friction element and the third friction element are in the engaged state and the first friction element and the fourth friction element are in the released state. Gear stage is formed,
When the control device shifts from the first gear stage to the second gear stage, before the input shaft of the automatic transmission reaches the rotational speed corresponding to the third gear stage, The control apparatus for an automatic transmission according to claim 1, wherein two friction elements are maintained in the predetermined state.   When the control device shifts from the first gear to the second gear, when the input shaft of the automatic transmission reaches a rotational speed corresponding to the third gear, The control device for an automatic transmission according to claim 2, wherein the engagement force of the friction element 3 is increased. A first gear is formed when the first friction element and the second friction element are engaged and the third friction element and the fourth friction element are released, and the first friction element is formed. An automatic transmission in which a second gear is formed when an element and the second friction element are in the released state and the third friction element and the fourth friction element are in the engaged state. A control device,
When the control device shifts from the first gear to the second gear, the control device releases the first friction element and maintains the second friction element in a semi-engaged state. A control device for an automatic transmission that increases an engagement force of the third friction element. The automatic transmission is third when the second friction element and the third friction element are in the engaged state and the first friction element and the fourth friction element are in the released state. Gear stage is formed,
When the control device shifts from the first gear stage to the second gear stage, before the input shaft of the automatic transmission reaches the rotational speed corresponding to the third gear stage, The control apparatus for an automatic transmission according to claim 4, wherein two friction elements are maintained in the half-engaged state.   When the control device shifts from the first gear to the second gear, when the input shaft of the automatic transmission reaches a rotational speed corresponding to the third gear, The control apparatus for an automatic transmission according to claim 5, wherein the engagement force of the friction element 3 is increased. A first gear is formed when the first friction element and the second friction element are engaged and the third friction element and the fourth friction element are released, and the first friction element is formed. An automatic transmission in which a second gear is formed when an element and the second friction element are in the released state and the third friction element and the fourth friction element are in the engaged state. A control device,
The control device releases the first friction element and maintains the second friction element in a predetermined state when shifting from the first gear stage to the second gear stage. A signal is transmitted to the automatic transmission so as to increase the engagement force of the friction element 3;
The control apparatus for an automatic transmission, wherein the predetermined state is a state in which slippage occurs in the second friction element when the third friction element is engaged . The automatic transmission is third when the second friction element and the third friction element are in the engaged state and the first friction element and the fourth friction element are in the released state. Gear stage is formed,
When the control device shifts from the first gear stage to the second gear stage, before the input shaft of the automatic transmission reaches the rotational speed corresponding to the third gear stage, The control apparatus for an automatic transmission according to claim 7, wherein two friction elements are maintained in the predetermined state.   When the control device shifts from the first gear to the second gear, when the input shaft of the automatic transmission reaches a rotational speed corresponding to the third gear, The control device for an automatic transmission according to claim 8, wherein the engagement force of the three friction elements is increased. A first gear is formed when the first friction element and the second friction element are engaged and the third friction element and the fourth friction element are released, and the first friction element is formed. An automatic transmission in which a second gear is formed when an element and the second friction element are in the released state and the third friction element and the fourth friction element are in the engaged state. A control device,
When the control device shifts from the first gear to the second gear, the control device releases the first friction element and maintains the second friction element in a semi-engaged state. A control device for an automatic transmission that transmits a signal to the automatic transmission so as to increase the engagement force of the third friction element. The automatic transmission is third when the second friction element and the third friction element are in the engaged state and the first friction element and the fourth friction element are in the released state. Gear stage is formed,
When the control device shifts from the first gear stage to the second gear stage, before the input shaft of the automatic transmission reaches the rotational speed corresponding to the third gear stage, The control apparatus for an automatic transmission according to claim 10, wherein two friction elements are maintained in the half-engaged state.   When the control device shifts from the first gear to the second gear, when the input shaft of the automatic transmission reaches a rotational speed corresponding to the third gear, The control device for an automatic transmission according to claim 11, wherein the engagement force of the friction element 3 is increased. The automatic transmission includes a fluid coupling whose input shaft is coupled to a power source, and a transmission mechanism connected to the output shaft of the fluid coupling,
The control device for an automatic transmission according to any one of claims 1 to 12, wherein the rotational speed of the input shaft of the automatic transmission is the rotational speed of the output shaft of the fluid coupling. A first gear is formed when the first friction element and the second friction element are engaged and the third friction element and the fourth friction element are released, and the first friction element is formed. An automatic transmission in which a second gear is formed when an element and the second friction element are in the released state and the third friction element and the fourth friction element are in the engaged state. A control method,
The control method is:
When shifting from the first gear to the second gear, releasing the first friction element and maintaining the second friction element in a predetermined state;
Increasing the engagement force of the third friction element while maintaining the second friction element in the predetermined state,
The method of controlling an automatic transmission, wherein the predetermined state is a state in which slippage occurs in the second friction element when the third friction element is engaged . A first gear is formed when the first friction element and the second friction element are engaged and the third friction element and the fourth friction element are released, and the first friction element is formed. An automatic transmission in which a second gear is formed when an element and the second friction element are in the released state and the third friction element and the fourth friction element are in the engaged state. A control method,
The control method is:
When shifting from the first gear stage to the second gear stage, releasing the first friction element and maintaining the second friction element in a semi-engaged state;
Increasing the engagement force of the third friction element while maintaining the second friction element in the half-engaged state.

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