JP5272772B2 - Shift control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shift controller for an automatic transmission capable of carrying out surely proper shifting. <P>SOLUTION: A gear position selecting part 71 selects a gear position capable of outputting, to driving wheels, gear position power in which a rotation speed of an engine 10 capable of generating the maximum power in every gear position by the maximum generative torque Tm, for example, when accelerating a vehicle, and a rotation speed of the engine 10 when generating a required power Pr, get nearest comprehensively, in the case where no gear position of the automatic transmission 20 giving a required driving force exists. The gear position capable of generating the gear position power nearest to the required power Pr is selected thereby, even when the required driving force is great and even when the required driving force can not generated, to reflect a request of a driver in travel of the vehicle to the utmost to the shift control for the automatic transmission 20. The proper shifting is carried out surely as a result thereof. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a shift control device for an automatic transmission. In particular, the present invention relates to a shift control device for an automatic transmission that shifts according to a driver's required driving force.

  Usually, when transmitting the output of the engine to the drive wheels, the vehicle has a transmission that can change the gear ratio according to the running state and transmit the rotation speed and torque to a desired rotation speed or torque. However, in recent vehicles, an automatic transmission that can automatically perform a shift by electronic control or the like is frequently used. This automatic transmission is automatically shifted based on the opening degree of an accelerator pedal operated by the driver and detection results of sensors provided in each part of the vehicle.

  For example, in the automatic transmission control device described in Patent Document 1, a gear stage having the lowest fuel consumption rate is selected as a target gear stage among gear stages whose required torque is equal to or less than the maximum torque of the engine, and the transmission is set to the target gear. If a predetermined condition is satisfied when the gear is shifted to a step and the accelerator opening is increased, the automatic transmission is prohibited from shifting. As a result, fuel efficiency can be reduced, and even when the engine load changes in a short cycle, such as when driving on an uphill road where the gradient changes frequently, the number of shifts can be reduced and a good shift feeling can be achieved. Can be secured.

JP 2006-336715 A

  However, depending on the running state of the vehicle, the required torque may be greater than the engine maximum torque. For example, when the driver demands a large driving force, the automatic transmission is controlled so that the gear ratio can achieve this driving force. On the other hand, the engine varies in performance. Therefore, when the driver is demanding a large driving force in this way, there is a case where the necessary torque is instructed to be larger than the engine performance assumed in advance in order to achieve the engine performance. In this case, since the required torque is larger than the maximum torque at each gear stage of the automatic transmission, it has been difficult to select an appropriate gear stage.

  The present invention has been made in view of the above, and an object of the present invention is to provide a shift control device for an automatic transmission that can perform an appropriate shift more reliably.

  In order to solve the above-described problems and achieve the object, a shift control device for an automatic transmission according to the present invention is provided so that the power of an engine, which is a power source when the vehicle is running, can be output to the drive wheel side. The gear stage capable of realizing a required driving force that is a driving force required by a driver of the vehicle when switching the gear stage of an automatic transmission having a plurality of gear stages capable of changing the rotational speed of the power. Required power calculation means for calculating the required power, which is an output to the driving wheel capable of realizing the required driving force, based on the required driving force, and for each gear stage that can be output to the driving wheel. A gear stage power calculation means for calculating a gear stage power that is a power, and a maximum torque or a minimum torque that can be generated for each engine speed among the plurality of gear stages. The engine speed capable of generating the gear speed power calculated by the gear speed power calculating means, and the engine speed and torque when generating the required power calculated by the required power calculating means, Gear stage selecting means for selecting, as the gear stage suitable for the current driving state, the gear stage capable of outputting to the drive wheels the gear stage power that is generally closest to the driving wheel. To do.

  In the present invention, when there is no gear stage that can achieve the required driving force, the engine speed that can generate the gear stage power by the torque that can be generated by the engine, and the engine speed when the required power is generated, The gear stage that can output to the drive wheels the gear stage power that gives the closest overall torque is selected as the gear stage suitable for the current driving state, so that the required driving force can be generated depending on the engine performance. Even if this is not possible, it is possible to select a gear that can generate the gear power closest to the required power. As a result, the driver's request can be reflected to the shift control of the automatic transmission to the maximum when the vehicle is traveling. As a result, an appropriate shift can be performed more reliably.

  Further, the shift control device for an automatic transmission according to the present invention is the shift control device for the automatic transmission, wherein the gear stage selecting means sends the required power, the gear stage power, and the generateable torque of the engine. When represented by the number of rotations and torque, among the plurality of gear stage powers, the gear stage power at which the distance between the intersection of the gear stage power and the generateable torque and the required power is the closest is the driving wheel. The gear stage that can be output with respect to is selected as the gear stage suitable for the current operating state.

  In the present invention, when there is no gear stage that can realize the required driving force, when selecting a gear stage suitable for the current operating state, the required power, the gear stage power, and the torque that can be generated are determined by the engine speed and the torque. Since the gear stage is selected on the basis of the relationship between the gear stage power and the generated torque and the required power when expressed by the above, it is possible to select an appropriate gear stage more reliably. As a result, an appropriate shift can be performed more reliably.

  The automatic transmission shift control device according to the present invention is the automatic transmission shift control device, wherein the automatic transmission further includes a torque converter having a lock-up mechanism, and the gear stage power The calculating means calculates the gear stage power for each lock-up state of the torque converter.

  In the present invention, since the gear stage power is calculated for each lockup state of the torque converter, the gear stage power can be calculated more accurately. Thereby, when selecting a gear stage based on gear stage power, an appropriate gear stage can be selected more reliably. As a result, an appropriate shift can be performed more reliably.

  Further, the shift control device for an automatic transmission according to the present invention is the shift control device for the automatic transmission, wherein the gear stage selecting means uses the maximum torque as the generateable torque when the vehicle is accelerated, When the vehicle decelerates, the gear stage is selected using the minimum torque as the generateable torque.

  In the present invention, when there is no gear stage capable of realizing the required driving force, the torque that can be generated when selecting a gear stage suitable for the current driving state is different between the time of acceleration and deceleration of the vehicle. Therefore, it is possible to select an appropriate gear stage in both cases of acceleration and deceleration of the vehicle. As a result, an appropriate shift can be performed more reliably.

  The shift control device for an automatic transmission according to the present invention has an effect that an appropriate shift can be performed more reliably.

FIG. 1 is a schematic diagram of a shift control device for an automatic transmission according to an embodiment of the present invention. FIG. 2 is a configuration diagram of a main part of the shift control device for the automatic transmission shown in FIG. FIG. 3 is an explanatory diagram for selecting a gear stage of the transmission during acceleration. FIG. 4 is an explanatory diagram for selecting a gear stage of the transmission during deceleration. FIG. 5 is a flowchart illustrating a processing procedure of the shift control device for the automatic transmission according to the embodiment.

  Embodiments of a shift control apparatus for an automatic transmission according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  FIG. 1 is a schematic diagram of a shift control device for an automatic transmission according to an embodiment of the present invention. The shift control device 1 shown in the figure is provided so as to be able to perform shift control of an automatic transmission 20 mounted on a vehicle (not shown). The automatic transmission 20 is connected to an engine 10 that is a power source. ing. As described above, the engine 10 provided as a power source during traveling of the vehicle is a reciprocating spark ignition type internal combustion engine using gasoline as fuel. The engine 10 is not limited to this. The engine 10 may be, for example, a spark ignition internal combustion engine using LPG (Liquefied Petroleum Gas) or alcohol as fuel, or a so-called rotary spark ignition internal combustion engine, A diesel engine may be used. The engine 10 is connected to an ECU (Electronic Control Unit) 60, and is provided so that the number of rotations and torque (output) can be controlled by the ECU 60.

  The automatic transmission 20 includes a torque converter 21, a transmission device 30, and a hydraulic control device 35. The power generated in the engine 10 and input to the automatic transmission 20 is provided so as to be transmitted to a transmission 30 which is a gear ratio variable means via a torque converter 21, and the power of the engine 10 is transmitted to the transmission 30. When transmitted, the number of revolutions is changed by the transmission 30 at a speed ratio selected according to the traveling condition of the vehicle, and the shifted torque is provided so as to be output to the drive wheels (not shown) of the vehicle. Yes.

  Of the automatic transmission 20 provided in this way, the torque converter 21 is provided rotatably and a pump 22 serving as an input side for the power of the engine 10, and is provided rotatably and an output side to the transmission 30. And a fluid transmission mechanism including a stator 25 disposed between the pump 22 and the turbine 23. Among these, the pump 22 is connected to an engine output shaft 11 that is an output shaft of the engine 10 and is connected to a cover 26 that rotates integrally with the engine output shaft 11. The engine output shaft 11, the cover 26, and the pump 22 is provided so that it can rotate integrally.

  Further, the turbine 23 is connected to a transmission input shaft 31 that is an input shaft of the transmission 30, and is provided so that the power of the engine 10 transmitted via the pump 22 can be transmitted to the transmission 30. That is, the turbine 23 is provided so that the power transmitted from the engine 10 can be output to the transmission 30 by transmitting the rotation of the turbine 23 to the transmission input shaft 31. The stator 25 is connected to a non-rotating case (not shown) via a one-way clutch (not shown), and the stator 25 can be rotated only in one direction by this one-way clutch.

  In addition, oil (not shown) that is a working fluid that transmits power is circulated between the pump 22, the turbine 23, and the stator 25, and the power transmitted from the engine 10 passes through this oil. So that they can communicate with each other. That is, the pump 22 is provided so as to be able to rotate when power from the engine 10 is inputted and to be able to transmit power by transmitting kinetic energy at the time of rotation to oil as a working fluid. . The turbine 23 is rotatably provided by transmitting power through oil that transmits kinetic energy by the pump 22, and further, the engine is transmitted through transmission of rotation to the transmission input shaft 31. The power transmitted from 10 is output to the transmission 30.

  Further, the torque converter 21 includes a lockup mechanism 27 capable of intermittently connecting the pump 22 and the turbine 23 that can rotate together. The lockup mechanism 27 includes a lockup clutch 28 that can rotate together with the turbine 23, and a cover 26 that can rotate integrally with the pump 22. Among these, the lock-up clutch 28 is disposed between the turbine 23 and the cover 26, and is engaged with or separated from the cover 26 by controlling the hydraulic pressure in the torque converter 21. . For this reason, when the lockup clutch 28 and the cover 26 are engaged, the pump 22 and the turbine 23 are engaged via the lockup clutch 28 and the cover 26. In this case, the power transmitted from the engine 10 is mechanically transmitted by the engagement between the pump 22 and the turbine 23.

  When the lock-up clutch 28 and the cover 26 are separated from each other, the power transmitted from the engine 10 is transmitted through oil circulating between the pump 22 and the turbine 23. As described above, the lockup mechanism 27 constituted by the lockup clutch 28 and the cover 26 engages and separates the lockup clutch 28 and the cover 26, so that the pump 22 and the turbine 23 are separated from each other. The power transmission is switched between fluid transmission, which is transmission using oil, and engagement transmission, which is transmission performed by engaging the pump 22 and the turbine 23.

  The automatic transmission 20 includes a planetary gear device that is a plurality of transmission elements, a plurality of friction engagement elements (clutch C1, clutch C2, clutch C3, clutch C4, brakes B1, B2) 40, and the like. The multi-stage transmission 30 is configured by combining the two. Here, the brake is the friction engagement element 40 attached to the casing of the transmission 30, and the clutch is not the casing of the transmission 30 but the friction engagement element 40 attached to the rotating shaft. The number of transmission elements and friction engagement elements 40 included in the transmission device 30 may be changed as appropriate according to the specifications of the automatic transmission 20.

  Further, the hydraulic control device 35 includes a linear solenoid valve 36 as a friction engagement element hydraulic pressure adjusting means for adjusting the hydraulic pressure of the control oil supplied to each friction engagement element 40. The hydraulic control device 35 is provided so as to be able to generate a hydraulic pressure for operating each friction engagement element 40, distributes the generated hydraulic pressure to a predetermined friction engagement element 40, and distributes the generated hydraulic pressure to the friction engagement element 40. It also has a function of adjusting the hydraulic pressure of the supplied control oil. The automatic transmission 20 includes a pump (not shown) that is connected to the linear solenoid valve 36 and supplies control oil stored in the automatic transmission 20 to the linear solenoid valve 36.

  In addition, the transmission 30 stops the rotating elements (carriers and ring gears) of the planetary gear device, which is a transmission element, by brakes B1, B2, and the like, which are friction engagement elements 40, and receives the power of the engine 10 The gear ratio can be changed by switching the rotation element of the device 30 with the clutches C1, C2, C3, C4, etc., which are the friction engagement elements 40. And the gear stage which is a gear stage is provided so that a change is possible by changing the combination of the rotation element to stop. That is, each combination of rotation and stop of the rotating elements is set as a gear stage of the automatic transmission 20, and the automatic transmission 20 can change the rotational speed of the power transmitted from the engine 10. There are a plurality of

  Since the automatic transmission 20 is provided as described above, the power generated by the engine 10 is input to the transmission 30 of the automatic transmission 20 via the torque converter 21. Moreover, the transmission 30 has a transmission output shaft 32 that is an output shaft of the transmission 30, and the transmission output shaft 32 is connected to a propeller shaft 45 of the vehicle. That is, the transmission output shaft 32 is an output shaft of the automatic transmission 20.

  Further, the engine 10 is provided with an engine speed sensor 15 which is an engine speed detecting means capable of detecting the speed of the engine output shaft 11. Further, the automatic transmission 20 includes the transmission input shaft rotational speed sensor 41 which is a transmission input shaft rotational speed detection means capable of detecting the rotational speed of the transmission input shaft 31 and the rotational speed of the transmission output shaft 32. A transmission output shaft rotational speed sensor 42 which is a transmission output shaft rotational speed detection means capable of detection is provided.

  These engine speed sensor 15, transmission input shaft speed sensor 41, transmission output shaft speed sensor 42, and linear solenoid valve 36 are connected to the ECU 60. Further, the ECU 60 includes an accelerator opening sensor 51 that is provided in the vicinity of an accelerator pedal 50 provided in a driver's seat of the vehicle and is an accelerator opening detecting means that can detect an accelerator opening that is an opening of the accelerator pedal 50. It is connected.

  FIG. 2 is a configuration diagram of a main part of the shift control device for the automatic transmission shown in FIG. The ECU 60 is provided with a processing unit 61, a storage unit 80, and an input / output unit 81, which are connected to each other and can exchange signals with each other. The engine speed sensor 15, the linear solenoid valve 36, the transmission input shaft speed sensor 41, the transmission output shaft speed sensor 42, and the accelerator opening sensor 51 connected to the ECU 60 are connected to the input / output unit 81. The input / output unit 81 inputs / outputs signals to / from these engine speed sensors 15 and the like. Further, the storage unit 80 stores a computer program for controlling the shift control device 1 of the automatic transmission 20. The storage unit 80 is a hard disk device, a magneto-optical disk device, a nonvolatile memory such as a flash memory (a storage medium that can be read only such as a CD-ROM), or a RAM (Random Access Memory). A volatile memory or a combination thereof can be used.

  The processing unit 61 includes a memory and a CPU (Central Processing Unit), and at least an accelerator opening that can acquire an accelerator opening that is an opening of the accelerator pedal 50 from a detection result of the accelerator opening sensor 51. An accelerator opening degree obtaining unit 62 that is a degree obtaining unit, an engine revolution number obtaining unit 63 that is an engine revolution number obtaining unit that obtains an engine revolution number from a detection result of the engine revolution number sensor 15, and a transmission output shaft revolution number. A vehicle speed acquisition unit 64 that is a vehicle speed acquisition unit that acquires the vehicle speed from the detection result of the sensor 42.

  The processing unit 61 shifts the transmission 30 with a required driving force calculation unit 65 that is a required driving force calculation unit that calculates a required driving force based on the accelerator opening acquired by the accelerator opening acquisition unit 62. The candidate gear stage, which is a candidate gear stage calculating means for calculating the candidate gear stage which is a candidate gear stage in the vehicle based on the vehicle speed acquired by the vehicle speed acquiring unit 64 and the required driving force calculated by the required driving force calculating unit 65. A required power calculation unit 67 that is a required power calculation unit that calculates a required power that is an output to a driving wheel capable of realizing the required driving force based on the required driving force calculated by the required driving force calculating unit 65. And a gear stage power calculation unit 68 that is a gear stage power calculation means for calculating a gear stage power that is a power for each gear stage that can be output to the drive wheels.

  The processing unit 61 also includes a gear stage that can generate the required driving force within the upper and lower limit torques of the engine and the gear stage that cannot generate the required driving force within the upper and lower limit torques of the engine among the candidate gear stages. And a candidate gear stage selecting unit 69 that is a candidate gear stage selecting means for selecting and a selection gear stage presence / absence determining means for determining whether or not there is a gear stage that satisfies the required driving force and can be selected at the time of shifting. When the selected gear stage presence / absence determining unit 70 and the selected gear stage presence / absence determining unit 70 determine that there is no gear stage that can be selected at the time of gear shifting, out of a plurality of gear stages, for each rotation speed of the engine 10. The engine speed capable of generating the gear stage power calculated by the gear stage power calculator 68 based on the maximum torque that can be generated or the minimum torque that can be generated, and the required power calculator The gear stage that can output to the drive wheels the gear stage power at which the engine speed and torque are the closest in total when generating the required power calculated in Step 7 is determined as the gear stage suitable for the current driving state. A gear stage selection unit 71 which is a gear stage selection means to select.

  The processing unit 61 controls the engine control unit 72 that is an internal combustion engine control unit that controls the operation of the engine 10 and the hydraulic pressure applied to the friction engagement element 40 of the automatic transmission 20 to control the automatic transmission 20. And a shift control unit 73 which is a hydraulic control means provided so as to be capable of shift control.

  The control of the shift control device 1 of the automatic transmission 20 controlled by the ECU 60 is performed by, for example, a memory in which the processing unit 61 incorporates the computer program in the processing unit 61 based on the detection result of the engine speed sensor 15 or the like. The control is performed by operating the linear solenoid valve 36 or the like according to the calculation result. At that time, the processing unit 61 appropriately stores a numerical value in the middle of the calculation in the storage unit 80, and takes out the stored numerical value and executes the calculation. In addition, when controlling the shift control apparatus 1 of the automatic transmission 20 in this way, it may be controlled by dedicated hardware different from the ECU 60 instead of the computer program.

  The shift control device 1 of the automatic transmission 20 according to this embodiment is configured as described above, and the operation thereof will be described below. While the vehicle is running, the speed and torque of the engine 10 are adjusted and the vehicle speed is adjusted by operating the accelerator pedal 50 with the foot. As described above, when the accelerator pedal 50 is operated, the stroke amount or the accelerator opening of the accelerator pedal 50 is detected by the accelerator opening sensor 51 provided in the vicinity of the accelerator pedal 50. The detection result by the accelerator opening sensor 51 is transmitted to the accelerator opening acquiring unit 62 included in the processing unit 61 of the ECU 60 and acquired by the accelerator opening acquiring unit 62. The accelerator opening acquired by the accelerator opening acquiring unit 62 is transmitted to the engine control unit 72 included in the processing unit 61 of the ECU 60, and the engine control unit 72 receives the detected accelerator opening and other sensor detection results. Based on this, the engine 10 is controlled.

  The engine 10 can be operated by being controlled by the engine control unit 72 in this way, but the power of the engine 10 controlled by the engine control unit 72 is externally driven by the rotation of the engine output shaft 11. Is output. The rotation of the engine output shaft 11 is first transmitted to the torque converter 21, and the torque converter 21 rotates and is transmitted to the transmission input shaft 31 via the torque converter 21.

  The rotation of the engine output shaft 11 transmitted to the transmission input shaft 31 via the torque converter 21 is transmitted to the transmission 30 by the transmission input shaft 31. Thereby, the power of the engine 10 is input to the transmission 30. Here, although the torque converter 21 is provided so as to be able to be locked up by the lock-up mechanism 27, when the power of the engine 10 is input to the transmission 30 through the torque converter 21, the torque converter 21 is in the lock-up state. Depending on whether or not there is, the power transmission path in the torque converter 21 differs.

  First, the case where the torque converter 21 is not in the lock-up state, that is, the case of fluid transmission in which the lock-up clutch 28 of the lock-up mechanism 27 is separated from the cover 26 will be described. The power of the engine 10 is torque from the engine output shaft 11. The cover 26, which is transmitted to the cover 26 of the converter 21 and to which the power is transmitted, rotates together with the pump 22 provided integrally with the cover 26 and rotatably. When the pump 22 rotates in this way, the pump 22 is sealed between the pump 22 and the turbine 23 and is circulated between the pump 22 and the turbine 23, and the movement of the pump 22 during the rotation is performed. Transmit energy. As a result, the oil flows, and the kinetic energy transmitted from the pump 22 when it circulates between the pump 22 and the turbine 23 is transmitted to the turbine 23.

  The turbine 23 to which kinetic energy is transmitted from the oil rotates by the transmitted kinetic energy. As described above, the turbine 23 rotated by the kinetic energy transmitted from the oil is connected to the transmission input shaft 31 of the transmission 30, and when the turbine 23 rotates, the turbine 23 rotates with the rotation of the turbine 23. The device input shaft 31 also rotates. Thereby, the power of the engine 10 is input to the transmission 30 via the torque converter 21.

  On the other hand, the case where the torque converter 21 is in the lock-up state, that is, the case of the engagement transmission in which the lock-up clutch 28 of the lock-up mechanism 27 is engaged with the cover 26 will be described. The power of the engine 10 transmitted to the cover 26 is transmitted from the cover 26 to the lockup clutch 28. The power transmitted to the lockup clutch 28 is transmitted from the lockup clutch 28 to the transmission input shaft 31. Thereby, when the torque converter 21 is in the lock-up state, the power transmitted from the engine 10 to the torque converter 21 is mechanically transmitted to the transmission input shaft 31 and is transmitted to the transmission 30 via the torque converter 21. Entered.

  Furthermore, the torque converter 21 can be slip-locked up. The slip lock-up will be described. The cover 26 and the lock-up clutch 28 can be engaged by friction engagement at the time of lock-up, but in the slip lock-up, the cover 26 and the lock-up clutch 28 are slipping. The state is engaged. That is, the slip lock-up causes the lock-up clutch 28 to be engaged with the cover 26 in a state where the pressure-bonding force of the lock-up clutch 28 to the cover 26 is weaker than when the lock-up is performed. Thus, the power of the engine 10 transmitted from the engine output shaft 11 to the cover 26 of the torque converter 21 is transmitted from the cover 26 to the lockup clutch 28 while sliding.

  Further, in this state, there may be a difference in rotation between the pump 22 and the turbine 23. However, when a difference in rotation occurs between the pump 22 and the turbine 23, the pump that rotates together with the cover 26 rotates. The power of the engine 10 transmitted from the engine output shaft 11 is also transmitted from the engine 22 to the turbine 23 via oil. In this way, the power transmitted to the lockup clutch 28 and the turbine 23 is transmitted to the transmission input shaft 31 and input to the transmission 30. As described above, in the slip lock-up state, the power of the engine 10 can be transmitted to the transmission 30 from both the lock-up clutch 28 and the turbine 23, and the lock-up state and the lock-up state are not performed. Power is transmitted in a state between.

  The motive power of the engine 10 input from the transmission input shaft 31 to the transmission 30 via the torque converter 21 is changed in rotational speed and torque by the transmission element of the transmission 30, so that the transmission 30 has a shift. Output from the device output shaft 32. Since the transmission output shaft 32 is connected to the propeller shaft 45 of the vehicle, the output from the transmission 30 is transmitted to the drive wheels of the vehicle via the propeller shaft 45. As a result, the drive wheels rotate and the vehicle travels.

  Further, during traveling of the vehicle, the shift control unit 73 included in the processing unit 61 of the ECU 60 controls the automatic transmission 20 and performs shift control according to the traveling state of the vehicle. Specifically, when the vehicle is running, the engine speed sensor 15 detects the speed of the engine output shaft 11 and the detection result is transmitted to the engine speed acquisition unit 63 of the processing unit 61 of the ECU 60 to acquire the engine speed. Obtained by the unit 63. Further, when the vehicle is traveling, the transmission output shaft rotational speed sensor 42 detects the rotational speed of the transmission output shaft 32. Since the transmission output shaft 32 and the drive wheels have a constant gear ratio, the rotational speed of the drive wheels can be estimated by detecting the rotational speed of the transmission output shaft 32, thereby reducing the vehicle speed. Can be estimated. For this reason, the transmission output shaft rotational speed sensor 42 is provided as a vehicle speed detection means capable of detecting the vehicle speed by detecting the rotational speed of the transmission output shaft 32. The rotational speed of the transmission output shaft 32 detected by the transmission output shaft rotational speed sensor 42 is transmitted to the vehicle speed acquisition unit 64 included in the processing unit 61 of the ECU 60, and the vehicle speed acquisition unit 64 performs a predetermined calculation. Get as vehicle speed.

  The shift control unit 73 operates the linear solenoid valve 36 according to the engine speed acquired by the engine speed acquisition unit 63, the vehicle speed acquired by the vehicle speed acquisition unit 64, and the like, thereby causing the friction engagement element 40 such as the clutch C1 to move. The gear ratio is changed and the gear stage is switched by switching the engagement and release of the friction engagement element 40 to switch the rotation and stop of the rotation element of the planetary gear device. Specifically, when the gear stage is switched, the linear solenoid valve 36 is operated to switch the release and engagement of the plurality of friction engagement elements 40 corresponding to the plurality of gear stages, thereby increasing the power of the engine 10. Switch the gear stage when outputting. When the gear stage is switched by switching between release and engagement of the friction engagement element 40 in this way, the friction engagement element 40 corresponding to the gear stage before the shift is released and corresponds to the gear stage after the shift. The gear stage is switched by engaging the friction engagement element 40. Thereby, the transmission 30 can change the rotation of the engine 10 input to the transmission input shaft 31 and output it from the transmission output shaft 32. That is, the transmission 30 is provided so as to be able to change gears by switching the gear stage based on the engagement and release of the friction engagement element 40.

  FIG. 3 is an explanatory diagram for selecting a gear stage of the transmission during acceleration. The gear stage of the transmission 30 is switched by switching the engagement and disengagement of the friction engagement element 40 in this way, but the switching of the gear stage during vehicle acceleration is a driving force requested by the driver. Switch based on the required driving force. Specifically, the required driving force can be generated, the engine 10 does not stall, the engine 10 does not overrev, and the engine 10 generates noise and vibration. A gear stage that is not rotated is calculated as a candidate gear stage by a candidate gear stage calculation unit 66 of the processing unit 61 of the ECU 60 based on the required driving force.

  Therefore, first, when the rotational speed of the engine 10 when the gear stage is set to a predetermined gear stage becomes the rotational speed at which the vehicle speed is the vehicle speed acquired by the vehicle speed acquisition unit 64, the rotational speed is If the engine speed becomes equal to or lower than the engine stall speed Rs, which is the stall rotation speed, or exceeds the overrev rotation speed Ro, which is the overrev speed, the gear stage is excluded from the candidate gear stages.

  Note that since the rotational speed of the engine 10 varies depending on the lock-up state of the torque converter 21 even when the vehicle speed is the same, this determination is made for each lock-up state. That is, for each gear stage, the torque converter 21 is in each of the lock-up state, slip-lock-up state, and lock-up state, that is, the torque converter mode in which only the fluid transmission is performed. In this case, the number of revolutions of the engine 10 is calculated, and it is determined whether or not the number of revolutions is equal to or less than the engine stall number Rs or equal to or greater than the overrev revolution number Ro. For this reason, for example, as shown in FIG. 3, the engine speed when the transmission 30 is shifted to the first speed or the second speed is overrevised in all the states of the lockup on Ln, the slip lockup Ls, and the torque converter mode Lf. When the rotational speed Ro is exceeded, the first speed and the second speed are excluded from the candidate gear stages.

  Further, noise and vibration during operation of the engine 10 increase when a predetermined torque is generated at a predetermined rotation speed. For this reason, when the gear stage is set to a predetermined gear stage, the rotational speed of the engine 10 becomes the rotational speed at which the vehicle speed can be made the vehicle speed acquired by the vehicle speed acquisition unit 64, and the torque of the engine 10 is the required driving force. If the rotation speed and torque state that can generate torque does not satisfy the N / V (Noise / Vibration) requirement, which is a requirement for an operation state that does not generate noise or vibration, this gear stage Is excluded from the candidate gear.

  For this reason, in the case where the required drive force is large and the maximum possible torque Tm that is the possible torque when the maximum torque that can be generated for each number of revolutions of the engine 10 is used, for example, as shown in FIG. As described above, when the transmission 30 is shifted to the sixth speed, and when the torque converter 21 is in the lock-up on Ln and the slip lock-up Ls, the N / V requirement is not satisfied. Excluded from the candidate gear.

  That is, when the gear stage of the transmission 30 is set to the sixth speed and the torque converter 21 is set to the lock-up on Ln, the N / V requirement NVo at the lock-up on, which is the N / V requirement at the lock-up on, is not satisfied. When the gear stage of the device 30 is set to the sixth speed and the torque converter 21 is set to the slip lockup Ls, the N / V requirement NVs at the slip lockup that is the N / V requirement at the time of the slip lockup is not satisfied. Is set to the sixth speed and the torque converter 21 is set to lock-up on Ln or slip lock-up Ls is excluded from the candidate gear stage.

  Further, among the candidate gear stages that are listed as candidates as described above, the gear stages that are within the upper and lower limit torques of the engine 10 are selected by the candidate gear stage selection unit 69 that the processing unit 61 of the ECU 60 has, and from among these, The gear stage with the best fuel efficiency is selected as the gear stage that is suitable for the current driving state and that can satisfy the driver's demand. If the gear stage selected in this way is the current gear stage of the transmission 30, the current gear stage is maintained, and if the selected gear stage is not the current gear stage, the shift control unit 73 The gear stage is switched by controlling the transmission 30.

  The gear stage of the transmission 30 is selected in this way, but there may be no gear stage that can be selected depending on the driving state of the vehicle. For example, when the driver requests a large driving force, there may be no gear stage that can realize the required driving force.

  In this case, the maximum power of each gear stage, that is, the maximum power of each gear stage that can be output to the drive wheels when each gear stage is selected, can generate the maximum power of each engine 10. The gear stage closest to the torque and the rotational speed of the required power Pr is selected as the rotational speed for each gear stage generated by the maximum torque Tm. This selection is performed by a gear stage selection unit 71 included in the processing unit 61 of the ECU 60. Further, when the gear stage is selected based on the required power Pr and the maximum power that can be generated at each gear stage, the gear stage including the lock-up state of the torque converter 21 is selected.

  That is, the torque of the engine 10 has a different maximum torque for each rotation speed of the engine 10, and even if the rotation speed of the engine 10 is the same rotation speed, the torque changes depending on the operation state such as the accelerator opening. . For this reason, the maximum torque Tm that can be generated by the engine 10 is the maximum torque for each rotation speed of the engine 10. When the maximum torque Tm that can be generated is represented by the rotational speed and torque of the engine 10, it is indicated by a curve in which the magnitude of the torque changes for each rotational speed of the engine 10 as shown in FIG.

  Further, the maximum power for each gear stage is set for each gear stage in relation to the rotational speed of the engine 10 capable of generating the maximum power and the torque. Further, the maximum power for each gear stage is set for each state of the torque converter 21, and in each gear stage, the torque converter 21 is set for each state of lock-up on Ln, slip lock-up Ls, and torque converter mode Lf. Is set to Therefore, the rotational speed of the engine 10 when the maximum power for each state of the gear stage and the torque converter 21 is generated with the maximum possible torque Tm is different for each state of the gear stage and the torque converter 21.

  For example, as described above, the 1st speed and the 2nd speed are excluded from the candidate gear speeds, and the 6th speed is excluded by the N / V requirement, so that the 3rd speed, the 4th speed, and the 5th speed become the candidate gear speeds. And the maximum power when the torque converter 21 is in the lock-up on Ln state at each gear stage, the third-speed lockup maximum power Pa3, the fourth-speed lockup maximum power Pa4, and the fifth-speed lockup maximum In the case of power Pa5, when these are represented by the rotation speed and torque of the engine 10, as shown in FIG.

  The rotational speed of the engine 10 when the maximum power for each state of the gear stage and the torque converter 21 is generated with the maximum possible torque Tm is the third speed lockup maximum power Pa3, the fourth speed lockup maximum power Pa4, and the fifth speed. This is the rotational speed at each intersection between the maximum lock-up power Pa5 and the maximum torque Tm that can be generated by the engine 10.

  Further, the required power Pr can be expressed by the rotation speed and torque of the engine 10 similarly to the maximum power for each gear stage, and the required power Pr is expressed by the rotation speed and torque of the engine 10 as shown in FIG. As described above, the maximum power for each gear stage is indicated by a curve in which the magnitude of torque changes for each rotation speed of the engine 10. When the gear stage is selected based on the required power Pr shown in this way, the intersection of the maximum power for each state of the gear stage and the torque converter 21 and the maximum torque Tm that can be generated by the engine 10, and the required power Pr The gear stage with the smallest distance from the curve is selected.

  That is, when the required power Pr, the maximum power for each gear stage, and the maximum torque Tm that can be generated are represented by the rotational speed and torque of the engine 10, the gear stage selection unit 71 determines the maximum power for each of the plurality of gear stages. Of these, the gear stage that can output to the drive wheels the maximum power at which the distance between the intersection of the maximum power and the maximum possible torque Tm and the required power Pr is the closest is selected as the gear stage suitable for the current driving state.

  For example, as illustrated in FIG. 3, the distance between the intersection of the third speed lockup maximum power Pa3 and the maximum possible torque Tm and the required power Pr is Da3, and the four speed lockup maximum power Pa4 and the maximum possible torque are generated. When the distance between the intersection with Tm and the required power Pr is Da4 and the distance between the intersection between the 5-speed lockup maximum power Pa5 and the maximum torque Tm that can be generated and the required power Pr is Da5, When the relationship is Da3 <Da4 <Da5, the gear stage selection unit 71 selects the third gear.

  In this way, the gear stage selection unit 71 determines the number of revolutions of the engine 10 that can generate the maximum power for each gear stage by the maximum torque Tm that can be generated, and the number of revolutions of the engine 10 when generating the required power Pr. The gear stage that can output the maximum power with which the torque is generally closest to the driving wheel is selected as the gear stage suitable for the current driving state.

  In other words, the difference between the rotational speed of the engine 10 when the maximum power for each gear stage is generated by the maximum possible torque Tm and the predetermined rotational speed of the engine 10 when the required power Pr is generated, and the generation in this case The difference between the maximum possible torque Tm and the torque of the engine 10 for generating the required power Pr is added with the same weighting, and the maximum power at which the added value becomes the smallest value is given to the drive wheels. Select a gear that can be output. That is, the difference between the rotational speed and torque of the engine 10 when the maximum power for each gear stage is generated by the maximum possible torque Tm and the predetermined rotational speed and torque of the engine 10 when the required power Pr is generated is a total. The gear stage that can output the maximum power to the driving wheel is selected as a gear stage suitable for the current driving state.

  FIG. 4 is an explanatory diagram for selecting a gear stage of the transmission during deceleration. Switching of the gear stage of the transmission 30 at the time of acceleration is performed based on the driver's required driving force in this way, but switching of the gear stage at the time of deceleration is also based on the driver's required driving force at the time of acceleration. Do it. That is, the deceleration force generated by the rotational resistance of the engine 10 at the time of deceleration, that is, the deceleration force by the engine brake becomes a driving force in the minus direction when the front of the vehicle is positive and the rear is negative. For this reason, the deceleration force caused by the engine brake generated by the driver reducing the accelerator opening during deceleration is also the driver's required driving force, and the gear stage switching during deceleration is also the driver's required driving force. Based on.

  That is, when the gear stage is switched during deceleration, the speed of the engine 10 when the gear stage is set to a predetermined gear stage is the vehicle speed acquired by the vehicle speed acquisition unit 64 in the same manner as when the gear stage is switched during acceleration. If the engine speed becomes the engine speed Rs or less or the overrev engine speed Ro or more, the gear stage is excluded from the candidate gear stages.

  To change the gear stage of the transmission 30 during deceleration, a gear stage that can satisfy the required driving force is selected from the candidate gear stages selected in this way. In other words, when the gear speed to be changed is selected from the gear stages where the driving force in the deceleration direction at the gear stage after the shift is less than or equal to the required driving force in the deceleration direction, and the driving force is viewed as an absolute value, The gear stage to be shifted is selected from the gear stages at which the driving force at the gear stage after the shift is greater than or equal to the required driving force. However, when selecting a gear stage to be switched at the time of deceleration, as in the case of selecting a gear stage to be switched at the time of acceleration, if the driver requests a large driving force in the deceleration direction, a gear that can realize the required driving force. There may be no steps.

  In this case, it is the lowest gear stage power at each gear stage, and the power at which the reduction force becomes the largest at each gear stage, that is, the lowest per gear stage that can be output to the drive wheels when each gear stage is selected. Among the powers, the gear stage in which the minimum speed for each gear stage generated by the minimum torque Ta at the time of idle-on is closest to the required power Pr is selected. This idle-on minimum torque Ta is a torque that can be generated when the lowest torque that can be generated for each number of revolutions of the engine 10 is used, and can be idled when the accelerator pedal 50 is fully closed. This is the minimum torque when fuel is injected.

  In other words, the torque of the engine 10 when the accelerator pedal 50 is fully closed and the engine is idling on is different in the minimum torque depending on the rotational speed of the engine 10, and the torque generally decreases as the rotational speed increases. In other words, the torque in the deceleration direction increases as the rotational speed of the engine 10 increases. For this reason, the idling-on minimum torque Ta is the minimum torque for each rotation speed of the engine 10. When the idling-on minimum torque Ta is expressed by the rotational speed and torque of the engine 10, the torque decreases as the rotational speed of the engine 10 increases as shown in FIG.

  Further, the minimum power for each gear stage is set for each gear stage in relation to the rotational speed and torque of the engine 10 that can generate the minimum power.

  Further, when the gear stage is selected based on the required power Pr and the minimum power that can be generated at each gear stage as described above, the gear stage including the lock-up state of the torque converter 21 is selected. In the shift control device 1 of the automatic transmission 20 according to the embodiment, a so-called deceleration lockup control is performed in which lockup is performed during deceleration. For this reason, the minimum power for each gear stage is the minimum power when the torque converter 21 is in the lock-up on state.

  The selection of the gear stage based on these will be described. For example, when selecting the gear stage at the time of deceleration, the 1st speed and the 2nd speed are excluded from the candidate gear stages when the overrev rotation speed Ro is exceeded. The 6th and 6th gears have the highest minimum power and the power in the deceleration direction is small, so they are excluded from the candidate gears, so the 3rd and 4th gears become the candidate gears. The minimum power Pi3 and the 4-speed lockup minimum power Pi4 are set. In this case, when the 3rd speed lockup minimum power Pi3 and the 4th speed lockup minimum power Pi4 are expressed by the rotation speed and the torque of the engine 10, the magnitude of the torque for each rotation speed of the engine 10 as shown in FIG. Is shown by a changing curve.

  The rotational speed of the engine 10 when the minimum power for each gear stage is generated with the minimum torque Ta at the time of idling on is determined by the three-speed lockup minimum power Pi3 and the four-speed lockup minimum power Pi4 and the idling-on minimum torque Ta. And the number of rotations at each intersection.

  Further, as shown in FIG. 4, the required power Pr is indicated by a curve in which the magnitude of the torque changes with the number of revolutions of the engine 10, similarly to the required power Pr during acceleration (FIG. 3). When the gear stage is selected based on the required power Pr shown as described above, the distance between the intersection of the minimum power for each gear stage and the minimum torque Ta at the time of idling and the curve of the required power Pr is the smallest. Select the gear stage.

  That is, the gear stage selection unit 71 represents the minimum power for each of the plurality of gear stages when the required power Pr, the minimum power for each gear stage, and the minimum torque Ta at the time of idle on are represented by the rotational speed and torque of the engine 10. The gear stage that can output to the drive wheels the lowest power at which the distance between the intersection of the lowest power and the lowest torque Ta at idle on and the required power Pr is the closest is selected as the gear stage suitable for the current driving state To do.

  For example, as illustrated in FIG. 4, the distance between the intersection of the 3rd speed lockup minimum power Pi3 and the idle torque minimum torque Ta and the required power Pr is Ds3, and the 4th speed lockup minimum power Pi4 and the idle power is on. In the case where the distance between the intersection with the minimum torque Ta and the required power Pr is Ds4 and the relationship between the distances is Ds3 <Ds4, the gear stage selection unit 71 sets the third gear stage. select.

  As described above, the gear stage selection unit 71 is capable of generating the minimum power for each gear stage by the minimum torque Ta at the time of idling on, and the rotation speed of the engine 10 when generating the required power Pr. The gear stage that can output the lowest power with which the torque and torque are closest together to the drive wheel is selected as the gear stage suitable for the current driving state.

  In other words, the difference between the rotational speed of the engine 10 when the minimum power for each gear stage is generated by the minimum torque Ta at the time of idling and the predetermined rotational speed of the engine 10 when the required power Pr is generated, and in this case The difference between the minimum torque Ta at the time of idling on and the torque of the engine 10 for generating the required power Pr is added with the same weighting, and the minimum power at which the added value becomes the smallest value is added to the driving wheel. Select the gear stage that can output. That is, the difference between the rotational speed and torque of the engine 10 when the minimum power for each gear stage is generated by the minimum torque Ta at the time of idling and the predetermined rotational speed and torque of the engine 10 when the required power Pr is generated is A gear stage that can output the lowest overall power to the driving wheels is selected as a gear stage suitable for the current driving state.

  In the shift control device 1 of the automatic transmission 20 according to the embodiment, since the lockup control at the time of deceleration is performed at the time of deceleration, the selection of the gear stage at the time of deceleration has been described for the state in which the torque converter 21 is locked up. When the deceleration lockup control is not performed, the gear stage is selected based on the minimum power for each state of the gear stage and the torque converter 21 as in the case of selecting the gear stage during acceleration.

  Further, in this description, a case is described in which the gear stage is selected based on the minimum torque Ta at the time of idling on, which is the minimum torque when injecting fuel capable of idling when the accelerator pedal 50 is fully closed. When performing fuel cut when the accelerator pedal 50 is fully closed, the engine torque Tf during F / C (FIG. 4), which is the minimum torque for performing fuel cut, is used in the same manner as during idling. Select the gear stage. The engine torque Tf at the time of F / C is also a torque that can be generated when the lowest torque that can be generated for each rotation speed of the engine 10 is used, similarly to the minimum torque Ta at the time of idling on.

  FIG. 5 is a flowchart illustrating a processing procedure of the shift control device for the automatic transmission according to the embodiment. Next, a control method of the shift control device 1 of the automatic transmission 20 according to the embodiment, that is, a processing procedure of the shift control device 1 will be described. Specifically, a processing procedure when the gear stage of the transmission 30 is selected by the transmission control device 1 of the automatic transmission 20 according to the embodiment will be described. The following processing is called and executed every predetermined period when each unit is controlled during driving of the vehicle.

  In the processing procedure of the shift control device 1 of the automatic transmission 20 according to the embodiment, first, the vehicle traveling state information is acquired (step ST101). As this traveling state information, for example, the accelerator opening, the rotational speed of the engine 10, the vehicle speed, and the like are acquired. Among these, the accelerator opening is the accelerator opening that is the opening of the accelerator pedal 50 operated by the driver, and the accelerator opening sensor 51 detects the accelerator opening, and the accelerator opening acquisition unit 62 included in the processing unit 61 of the ECU 60 is detected. Get in. Further, the rotational speed of the engine 10 is obtained by detecting the rotational speed of the engine output shaft 11 by the engine rotational speed sensor 15 and acquiring the detection result by the engine rotational speed acquisition unit 63 included in the processing unit 61 of the ECU 60. The vehicle speed is detected by the transmission output shaft rotational speed sensor 42 using the transmission output shaft rotational speed sensor 42, and the detection result is acquired by the vehicle speed acquisition unit 64 included in the processing unit 61 of the ECU 60.

  Next, the required driving force is calculated (step ST102). The required driving force is calculated by a required driving force calculator 65 included in the processing unit 61 of the ECU 60. The required driving force calculation unit 65 calculates a required driving force that is a driving force requested by the driver based on the accelerator opening obtained by the accelerator opening obtaining unit 62. The required driving force includes not only the driving force at the time of acceleration but also the driving force in the deceleration direction that is a force that generates a deceleration at the time of deceleration.

  Next, a candidate gear stage is calculated (step ST103). The calculation of the candidate gear stage is performed by a candidate gear stage calculation unit 66 included in the processing unit 61 of the ECU 60. The candidate gear stage calculation unit 66 can generate a driving force close to the required driving force from the vehicle speed acquired by the vehicle speed acquisition unit 64 and the required driving force calculated by the required driving force calculation unit 65, and the engine 10 The gear speed at which the engine 10 does not stall, the rotational speed of the engine 10 does not become overrev, and the rotational speed of the engine 10 does not generate noise or vibration is calculated as a candidate gear speed.

  This calculation is preliminarily stored in the storage unit 80 of the ECU 60, and is calculated based on a map represented by the relationship between the rotational speed and torque of the engine 10 as shown in FIGS. Specifically, when the vehicle speed is the vehicle speed acquired by the vehicle speed acquisition unit 64, the rotation speed of the engine 10 at each gear stage of the transmission 30 is calculated, and the calculated rotation speed becomes equal to or less than the engine rotation speed Rs or the overrev rotation speed. A gear stage that exceeds Ro is excluded from the candidate gear stages. Further, gear speeds at which the calculated engine speed of the engine 10 does not satisfy the N / V requirement NVo at the time of lockup ON or the N / V requirement NVs at the time of slip lockup are also excluded from the candidate gear speeds. Further, the required driving force is compared with the driving force that can be generated at each gear stage, and the gear stage that cannot generate the required driving force is also excluded from the candidate gear stages. The candidate gear stage calculation unit 66 calculates the candidate gear stage as described above.

  Next, candidate gear stages within the engine operating range are selected (step ST104). This selection is performed by a candidate gear stage selection unit 69 included in the processing unit 61 of the ECU 60. The candidate gear stage selection unit 69 calculates the torque of the engine 10 when the required driving force is generated at each candidate gear stage calculated by the candidate gear stage calculation unit 66, and the calculated torque is within the upper and lower limit torques of the engine 10. To select candidate gears within the engine operating range. Of the candidate gear stages, the gear stage in which the torque of the engine 10 when generating the required driving force is within the upper and lower limit torques of the engine 10 is the gear stage selected during acceleration or deceleration.

  Next, it is determined whether there is no solution (step ST105). This determination is performed by a selection gear stage presence / absence determination unit 70 included in the processing unit 61 of the ECU 60. The selected gear stage presence / absence determining unit 70 determines whether there is a gear stage that can be selected when the gear stage is selected by the candidate gear stage selecting unit 69, that is, a solution for selecting a gear stage that satisfies the required driving force. It is determined whether or not there is. If it is determined by this determination that there is a gear stage to be selected and there is a solution, the processing procedure is exited.

  If it is determined by the determination at the selected gear stage presence / absence determination unit 70 (step ST105) that there is no solution in selecting a gear stage that satisfies the required driving force, next, the required power is calculated (step ST106). ). The required power is calculated by a required power calculation unit 67 included in the processing unit 61 of the ECU 60 based on the required driving force calculated by the required driving force calculation unit 65. The required power calculation unit 67 calculates the required power, which is an output to the driving wheel necessary for generating the required driving force, using the relationship between the rotational speed of the engine 10 and the torque as shown in FIGS. calculate.

  Next, the power of the candidate gear stage is calculated (step ST107). The calculation of the power of the candidate gear stage is performed by a gear stage power calculation unit 68 included in the processing unit 61 of the ECU 60. The gear stage power calculation unit 68 calculates the maximum power of each candidate gear stage from among the candidate gear stages calculated by the candidate gear stage calculation unit 66 when the vehicle is accelerating, and In this case, among the candidate gear stages calculated by the candidate gear stage calculation unit 66, the minimum power of each candidate gear stage is calculated. The maximum power and the minimum power of these gear stages are preset in a map state using the relationship between the rotational speed and torque of the engine 10 as shown in FIG. 3 and FIG. 4, and are stored in the storage unit 80 of the ECU 60. ing. The gear stage power calculation unit 68 calculates the maximum power and the minimum power of the candidate gear stage by referring to a map stored in the storage unit 80. In addition, when calculating the power of a candidate gear stage in this way, it calculates for every lockup state including the lockup state of the torque converter 21.

  Next, a gear stage is selected (step ST108). The gear stage is selected by a gear stage selection unit 71 included in the processing unit 61 of the ECU 60. The gear stage selection unit 71 calculates the torque and the rotational speed when the maximum power of the plurality of candidate gear stages calculated by the gear stage power calculation unit 68 is generated with the maximum possible torque Tm, or calculated by the gear stage power calculation unit 68. Torque and rotational speed when the minimum power of the plurality of candidate gears is generated with minimum torque Ta at idle on and engine torque Tf at F / C, and the torque and rotational speed of the required power calculated by the required power calculation unit 67 And the candidate gear stage with the shortest distance is selected. Specifically, the gear selection unit 71 determines the intersection between the maximum power of the plurality of candidate gears calculated by the gear power calculation unit 68 and the maximum possible torque Tm, and the required power calculated by the required power calculation unit 67. The distance from Pr, or the intersection of the minimum power of the plurality of candidate gears calculated by the gear stage power calculation unit 68 and the engine torque Tf at the time of idle-on minimum torque Ta and F / C, and the required power calculation unit 67 The calculated distance to the required power Pr is compared on a map representing these, and the candidate gear stage with the smallest distance is selected. When a gear stage is selected by the gear stage selection unit 71, the processing procedure is exited.

  If it is determined by the selection gear stage presence / absence determination unit 70 (step ST105) that there is a solution for selecting a gear stage, or if a gear stage is selected by the gear stage selection unit 71 (step ST108). The gear shift control unit 73 controls the hydraulic pressure control device 35 of the transmission device 30 in another processing procedure for actually shifting the transmission device 30 to shift to the selected gear stage.

  The shift control device 1 of the automatic transmission 20 described above is provided for each gear stage according to the torque that can be generated by the engine 10 such as the maximum torque Tm that can be generated and the minimum torque Ta at the time of idling when there is no gear stage that can achieve the required driving force. The speed of the engine 10 that can generate the maximum power and the minimum power of the gear 10 and the speed of the engine 10 and the torque when the required power Pr is generated are the closest together. Is selected by the gear selection unit 71 as a gear suitable for the current driving state. Thereby, even when the required driving force is large and the required driving force cannot be generated due to the performance of the engine 10, it is possible to select a gear stage that can generate the gear stage power closest to the required power Pr, The driver's request when the vehicle is traveling can be reflected to the maximum in the shift control of the automatic transmission 20. As a result, an appropriate shift can be performed more reliably.

  Further, when there is no gear stage that can realize the required driving force, an appropriate gear stage can be selected and an appropriate shift can be performed more reliably, so that the performance of the engine 10 can be used up to the maximum. In addition, the driver's request is reflected in the shift control of the automatic transmission 20 as much as possible, and by performing an appropriate shift, the feeling during driving of the vehicle can be improved.

  Further, when there is no gear stage capable of realizing the required driving force, when selecting a gear stage suitable for the current operating state, the gear stage power and generation when each power is expressed by the rotation speed and torque of the engine 10 are generated. The gear stage that can output the gear stage power with the closest distance between the intersection with the possible torque and the required power Pr to the drive wheel is selected as the gear stage suitable for the current driving state. This makes it possible to more easily select the gear power at which the rotational speed and torque of the engine 10 when generating the required power Pr are closest to each other. By selecting a gear that can be output, an appropriate gear can be selected easily and reliably. As a result, an appropriate shift can be performed more reliably.

  Further, since the gear stage power is calculated for each lock-up state of the torque converter 21, the gear stage power can be calculated more accurately. In other words, when the gear stage power is calculated, if the lock-up state is different even if the gear stage is the same, it is handled as a different gear stage power. The maximum power and the minimum power that can be output can be calculated more accurately. Thereby, when selecting a gear stage based on gear stage power, an appropriate gear stage can be selected more reliably. As a result, an appropriate shift can be performed more reliably.

  In addition, when there is no gear stage that can achieve the required driving force, the maximum torque that can be generated for each engine speed when the vehicle is accelerated is the torque that can be used when selecting a gear stage suitable for the current driving state. A certain maximum torque Tm that can be generated is used, and when the vehicle decelerates, the minimum torque Ta that can be generated at each engine speed and the minimum torque Ta at the time of F / C and the engine torque Tf at the time of F / C are used. By using different torques that can be generated when the vehicle is accelerating and decelerating, it is possible to ensure that the gear stage power and the required power regardless of whether the vehicle is accelerating or decelerating. Pr can be compared, and an appropriate gear can be selected in both cases of acceleration and deceleration of the vehicle. As a result, an appropriate shift can be performed more reliably.

  As described above, the shift control device for an automatic transmission according to the present invention is useful for controlling an automatic transmission that shifts according to the required driving force requested by the driver, and in particular, performs an appropriate shift. It is suitable for expanding the area and performing more reliable shifting.

DESCRIPTION OF SYMBOLS 1 Shift control apparatus 10 Engine 20 Automatic transmission 21 Torque converter 27 Lockup mechanism 30 Transmission 35 Hydraulic control apparatus 40 Friction engagement element 50 Accelerator pedal 51 Accelerator opening sensor 60 ECU
61 Processing Unit 62 Accelerator Opening Acquisition Unit 63 Engine Speed Acquisition Unit 64 Vehicle Speed Acquisition Unit 65 Required Driving Force Calculation Unit 66 Candidate Gear Calculation Unit 67 Required Power Calculation Unit 68 Gear Stage Power Calculation Unit 69 Candidate Gear Stage Selection Unit 70 Selection Gear stage presence / absence determination unit 71 Gear stage selection unit 72 Engine control unit 73 Shift control unit 80 Storage unit

Claims (3)

When switching the gear stage of an automatic transmission provided with a plurality of gear stages capable of shifting the rotational speed of the engine, which is capable of outputting the power of an engine, which is a power source during traveling of the vehicle, to the drive wheel side In addition, when there is no gear stage that can realize the required driving force that is required by the driver of the vehicle, the required power that is the output to the drive wheels that can realize the required driving force is used as the required driving force. A required power calculation means for calculating based on;
Gear stage power calculating means for calculating a gear stage power that is a power for each of the gear stages that can be output to the drive wheel;
Among the plurality of gear stages, a maximum torque or a minimum torque that can be generated for each engine speed , the required power calculated by the required power calculation means, and the gear stage power calculation means When the calculated gear stage power is represented by the rotational speed and torque of the engine, the distance between the required power and the intersection of the gear stage power and the generateable torque among the plurality of gear stage powers Gear stage selection means for selecting, as the gear stage suitable for the current driving state, the gear stage that can output the gear stage power that is closest to the driving wheel;
A shift control device for an automatic transmission, comprising: Further, the automatic transmission has a torque converter having a lock-up mechanism,
The shift control device for an automatic transmission according to claim 1, wherein the gear stage power calculation means calculates the gear stage power for each lock-up state of the torque converter. The gear stage selection means uses the maximum torque as the possible torque when the vehicle is accelerated and selects the gear stage using the minimum torque as the possible torque when the vehicle is decelerated. The shift control device for an automatic transmission according to claim 1 or 2 .

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