JP2010077997A - Control device for automatic transmission - Google Patents

Abstract

In a control device for an automatic transmission, appropriate kick-down control is enabled to improve drivability and improve fuel efficiency.
When a kick-down operation by a driver is detected, a target shift stage after a predetermined time has elapsed from the kick-down operation is set based on an accelerator opening and a vehicle speed, and the target shift stage is set to the current shift stage. The shift down is executed based on the throttle opening and the vehicle speed when the speed is on the lower speed side, while the shift down is prohibited when the target speed is the same as the current speed or on the high speed side.
[Selection] Figure 1

Description

  The present invention relates to a control device for an automatic transmission, and more particularly to control when a kick-down operation in which an accelerator pedal is depressed beyond a predetermined opening is performed.

  In vehicles equipped with an automatic transmission control device, in general, the target driving force of the vehicle according to the accelerator opening (or throttle opening) according to the accelerator pedal depression operation by the driver and the current vehicle speed. Is set, and the engine speed and the gear position are set based on the target driving force. In this automatic transmission control device, a kick-down shift region is set. That is, when the vehicle is traveling at a constant vehicle speed, when the driver performs a kick-down operation that depresses the accelerator pedal to the fully open position, downshift control is performed in which the gear stage is a gear stage that can obtain the maximum driving force. The

  However, depending on the running state of the vehicle, this downshift control may deteriorate the riding comfort. For example, the driver gradually depresses the accelerator pedal even though he / she wants to accelerate at the current gear position.When the accelerator opening exceeds a predetermined value, it is determined that the kick-down operation is performed, downshift control is executed, The comfort gets worse. As what solves such a problem, there exists a thing described in the following patent document 1, for example. The shift control device for an automatic transmission described in Patent Document 1 controls the shift according to a shift pattern having a kick-down shift region when the change speed of the throttle opening is larger than a predetermined value, Appropriate downshift control is enabled by controlling the shift according to a shift pattern that does not have a kickdown shift region when the change speed is smaller than a predetermined value.

Japanese Patent Laid-Open No. 04-194448

  In the conventional shift control device for an automatic transmission described above, a shift pattern having a kick-down shift region and a shift pattern not having a kick-down shift region are prepared in advance, and the shift pattern is switched according to the change speed of the throttle opening. Yes. In this case, when a shift pattern having a kick-down shift region is selected, the gear is shifted up according to the accelerator opening and the vehicle speed after being shifted down. However, the ride comfort may be deteriorated even by this series of controls. . In other words, if a busy shift phenomenon occurs in which a shift up is performed immediately after a shift down, or a shift down and a shift up are repeated, the driver feels uncomfortable and the fuel consumption is also deteriorated.

  In order to suppress the occurrence of the busy shift phenomenon, it is conceivable to provide a hysteresis between the shift-down determination and the shift-up determination. However, if this hysteresis is reduced, it is advantageous in terms of fuel consumption, but the speed change operation becomes frequent and the drivability is deteriorated. On the other hand, increasing the hysteresis is advantageous in terms of drivability, but there is a possibility that the speed change operation becomes sluggish and fuel consumption is deteriorated. This makes it difficult to set hysteresis and complicates the control.

  The present invention is intended to solve such a problem, and an object of the present invention is to provide a control device for an automatic transmission that enables appropriate kickdown control to improve drivability and improve fuel efficiency. And

  In order to solve the above-described problems and achieve the object, a control device for an automatic transmission according to the present invention is a control device for an automatic transmission that shifts and outputs a driving force of an internal combustion engine. Kick-down operation detecting means for detecting, kick-down control executing means for executing shift down based on the throttle opening and the vehicle speed when the kick-down operation is detected, and accelerator opening when the kick-down operation is detected And a target shift speed setting means for setting a target shift speed after a predetermined time elapses from the kick-down operation based on the vehicle speed, and downshifting when the target shift speed is the same as or higher than the current shift speed And kick-down control suppression prohibiting means for suppressing or prohibiting.

  In the control apparatus for an automatic transmission according to the present invention, the predetermined time is set in consideration of a busy shift feeling of a driver in a time required for downshifting.

  In the control apparatus for an automatic transmission according to the present invention, the predetermined time is set in accordance with a shift speed, a shift mode, and a vehicle speed accelerator opening.

  In the control device for an automatic transmission according to the present invention, the target gear position setting means estimates a target vehicle speed after a predetermined time has elapsed based on the current accelerator opening and the current vehicle speed, and the target vehicle speed and the current accelerator opening. The target shift speed is set based on the degree.

  In the automatic transmission control device of the present invention, a running resistance detecting means for detecting a running resistance of the vehicle is provided, and the target shift speed setting means is a target after a predetermined time has elapsed based on the accelerator opening, the vehicle speed, and the running resistance. It is characterized by setting a gear position.

  According to the control device for an automatic transmission of the present invention, when a kickdown operation of the driver is detected, a target shift stage after a predetermined time elapses from the kickdown operation is set based on the accelerator opening and the vehicle speed. When the target shift speed is the same as the current shift speed or on the high speed side, downshifting is suppressed or prohibited. Therefore, if the target shift speed is lower than the current shift speed, shift down is permitted, while if the target shift speed is the same as the current shift speed or higher, the shift down is suppressed or prohibited. Therefore, it is possible to improve drivability by enabling appropriate kickdown control and to improve fuel efficiency.

  Embodiments of an automatic transmission control device according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this Example.

  1 is a schematic configuration diagram illustrating a control device for an automatic transmission according to a first embodiment of the present invention, FIG. 2 is a flowchart illustrating kickdown control in the control device for the automatic transmission according to the first embodiment, and FIG. FIGS. 3A and 3B are time charts showing kickdown control in the control device for the automatic transmission according to the first embodiment.

  In the automatic transmission control apparatus according to the first embodiment, as shown in FIG. 1, an engine 11 as an internal combustion engine is configured by fastening a cylinder head on a cylinder block, and is provided with a plurality of cylinders. Then, a piston is fitted to each cylinder so as to be movable up and down, and a crankshaft is connected to each piston via a connecting rod.

  A stepped transmission 13 is connected to the engine 11 via a torque converter 12, and the torque converter 12 and the transmission 13 constitute an automatic transmission 14. A differential gear 15 is connected to the automatic transmission 14 via a propeller shaft, left and right drive shafts 16 are connected via the differential gear 15, and left and right drive wheels 17 are connected to the drive shaft 16. .

  Therefore, when the engine 11 is driven, the driving force is output from the crankshaft and input to the input shaft of the transmission 13 via the torque converter 12, where the speed is reduced to a predetermined gear ratio. Then, the driving force after deceleration is output from the output shaft of the automatic transmission 14 to the propeller shaft, and is transmitted from the propeller shaft to the left and right drive shafts 16 via the differential gear 15 to drive and rotate the left and right drive wheels 17. be able to.

  An electronic control unit (ECU) 21 is mounted on the vehicle, and the ECU 21 can control the fuel injection timing by the injector, the ignition timing of the spark plug, and the like. The fuel injection amount, the injection timing, the ignition timing, and the like are determined based on the engine operating state such as the accelerator opening and the engine speed.

  That is, an air flow sensor 22 is mounted on the upstream side of the intake pipe, and the measured intake air amount is output to the ECU 21. The electronic throttle device is provided with a throttle position sensor 23, and the accelerator pedal is provided with an accelerator position sensor 24, which outputs the current throttle opening and accelerator opening to the ECU 21.

  Further, the ECU 21 can control the gear ratio and the shift timing by controlling the hydraulic control circuit 31 of the automatic transmission 14, and based on the detected shift position, throttle opening, accelerator opening, vehicle speed, and the like. Shift stage, shift timing, etc. are determined.

  That is, the vehicle is provided with a shift lever device that is operated by a driver, and this shift lever device is operated to operating positions such as parking (P), reverse (R), neutral (N), and drive (D). It is possible. This shift lever device is provided with a shift position sensor 32 that can detect the operation positions P, R, N, and D, and an operation position signal is output to the ECU 21. Further, the vehicle is provided with a vehicle speed sensor 33 that detects the speed of the vehicle, and the current vehicle speed is output to the ECU 21.

  By the way, in a vehicle equipped with an automatic transmission, a gear position is set according to a throttle opening and a vehicle speed, and a gear shift is executed at a predetermined timing. Further, when the driver performs a kick-down operation in which the accelerator pedal is depressed to the vicinity of the fully open position, a downshift is performed in which the gear position is a gear position at which the maximum driving force can be obtained. In this kick-down control, the ride comfort may be deteriorated depending on the traveling state of the vehicle. In other words, if a busy shift phenomenon occurs in which a shift up is performed immediately after a shift down, or a shift down and a shift up are repeated, the driver feels uncomfortable and the fuel consumption is also deteriorated.

  Therefore, in the control device for the automatic transmission according to the first embodiment, the kickdown operation detecting means for detecting the kickdown operation by the driver, and the shift down is executed based on the throttle opening and the vehicle speed when the kickdown operation is detected. Kickdown control execution means for performing, and target gear position setting means for setting a target gear position after a predetermined time elapses from the kickdown operation based on the accelerator opening and the vehicle speed when the kickdown operation is detected; In addition, there is provided kick down control prohibiting means (kick down control suppression prohibiting means) for prohibiting downshifting when the target shift speed is the same as the current shift speed.

  The ECU 21 functions as the kick down operation detecting means, the kick down control executing means, the target gear position setting means, and the kick down control suppression prohibiting means.

  That is, when the ECU 21 detects a kick-down operation by the driver (kick-down operation detecting means), the ECU 21 sets a target gear position after a predetermined time elapses from the kick-down operation based on the accelerator opening and the vehicle speed (target Shift stage setting means), and when the target shift speed is lower than the current shift speed, shift down is executed based on the throttle opening and the vehicle speed (kick down control execution means), while the target shift speed is When it is the same as the gear position, the shift down is prohibited (kick down control prohibiting means).

  In this case, the predetermined time is set in consideration of the busy shift feeling of the driver in the time required for the automatic transmission 14 to shift down. That is, when there is a kick-down operation by the driver and shift down is performed, the transmission 13 increases the output rotational speed on the upper gear stage side to approximate the output rotational speed on the lower gear side, The gear ratio is switched at a predetermined shift point, and the time required for the automatic transmission 14 to shift down is to increase the output speed on the upper gear side and approximate the output speed on the lower gear side. It's time. The driver's busy shift feeling is a time when the driver feels that the driver feels uncomfortable for a long time from the start of the downshift to the completion of the upshift when the driver performs a kickdown operation.

  The predetermined time is set according to parameters such as a shift mode, a shift speed, a vehicle speed accelerator opening, a transmission oil temperature, and an engine water temperature. For example, the predetermined time is set shorter in the sport mode than in the normal shift mode. In this case, a control map corresponding to each parameter may be provided.

  In the automatic transmission control apparatus according to the first embodiment, the ECU 21 estimates a target vehicle speed after a predetermined time based on the current accelerator opening and the current vehicle speed, and sets the target vehicle speed and the current accelerator opening. Based on this, the target gear position is set.

  Here, the kick down control by the control apparatus for the automatic transmission according to the first embodiment will be described based on the flowchart of FIG.

  In the kickdown control by the automatic transmission control device of the first embodiment, as shown in FIG. 2, in step S11, the ECU 21 determines whether or not there is a kickdown determination by the normal shift control. Here, it is determined whether or not a kick-down operation by the driver is detected based on the change amount of the accelerator opening. Here, when the kick down operation is not detected, the routine exits without doing anything.

  On the other hand, if a kick down operation is detected in step S11, the vehicle acceleration is calculated from the accelerator opening and the current vehicle speed in step S12, and a predetermined time T1 set in advance after the kick down operation is detected. Estimate the vehicle speed after elapse of. Subsequently, in step S13, a shift determination is made from the vehicle speed after the elapse of the predetermined time T1 and the current accelerator opening, and the target gear position after the elapse of the predetermined time T1 is estimated.

  In step S14, the ECU 21 compares the current gear stage g0 with the target gear stage g2, and when the target gear stage g2 is on the lower speed side than the current gear stage g0, the ECU 21 proceeds to step S15, where the throttle opening. The gear stage g1 is set based on the speed and the vehicle speed, and downshifting to this gear stage g1 is executed. On the other hand, when the target gear stage g2 is the same as the current gear stage g0 in step S14, downshifting is prohibited in step S16.

  Here, the kickdown control by the control apparatus for the automatic transmission according to the first embodiment will be specifically described based on the time charts of FIGS. 3-1 and 3-2.

  In the kickdown control by the automatic transmission control device of the first embodiment, as shown in FIG. 3-1, when the driver performs a kickdown operation at time t1, the accelerator opening increases and the vehicle speed also increases. To do. At this time, the target gear position after the elapse of the predetermined time T1 is estimated from the accelerator opening and the current vehicle speed. Since the target gear stage g2 = 2 is on the lower speed side than the current gear stage g0 = 3, downshifting to this gear stage g2 = 2 is executed. Then, at time t2, a shift up is executed.

  On the other hand, as shown in FIG. 3-2, when the driver performs a kick-down operation at time t1, the accelerator opening increases and the vehicle speed also increases. At this time, the target gear position after the elapse of the predetermined time T1 is estimated from the accelerator opening and the current vehicle speed. Since the target gear stage g2 = 3 is the same as the current gear stage g0 = 3, downshifting to the immediately preceding gear stage g1 = 2 (a chain line in FIG. 3-2) is prohibited.

  As described above, in the control apparatus for the automatic transmission according to the first embodiment, when the kickdown operation by the driver is detected, the target after the elapse of a predetermined time set in advance from the kickdown operation based on the accelerator opening and the vehicle speed. When a shift stage is set and the target shift stage is lower than the current shift stage, a shift down is executed based on the throttle opening and the vehicle speed, while when the target shift stage is the same as the current shift stage, a shift is performed. Down is prohibited.

  Therefore, if the target shift speed is lower than the current shift speed, the shift down is permitted. On the other hand, if the target shift speed is the same as the current shift speed, the shift down is prohibited, thereby preventing the busy shift phenomenon. Occurrence can be prevented and appropriate kickdown control can be performed, drivability can be improved, and fuel consumption can be improved by suppressing frequent shifts.

  Further, in the automatic transmission control apparatus according to the first embodiment, the predetermined time is set in consideration of the busy shift feeling of the driver with the time required for the downshift. Therefore, it is possible to determine whether or not downshifting is possible without causing discomfort to the driver, and both improvement in drivability and improvement in fuel consumption can be achieved.

  In the automatic transmission control apparatus according to the first embodiment, the predetermined time is set according to the shift speed, the shift mode, and the vehicle speed accelerator opening. Therefore, appropriate kickdown control can be performed by changing the predetermined time according to the traveling state of the vehicle.

  In the automatic transmission control apparatus according to the first embodiment, the target vehicle speed after a predetermined time has elapsed is estimated based on the current accelerator opening and the current vehicle speed, and the target vehicle speed is determined based on the target vehicle speed and the current accelerator opening. The gear position is set. Accordingly, it is possible to easily calculate the target vehicle speed after a predetermined time has elapsed.

  FIG. 4 is a schematic configuration diagram illustrating a control device for an automatic transmission according to a second embodiment of the present invention, and FIG. 5 is a flowchart illustrating kickdown control by the control device for the automatic transmission according to the second embodiment. In addition, the same code | symbol is attached | subjected to the member which has the same function as what was demonstrated in the Example mentioned above, and the overlapping description is abbreviate | omitted.

  In the control apparatus for an automatic transmission according to the second embodiment, a running resistance detecting means (ECU 21) for detecting a running resistance of the vehicle is provided, and the ECU 21 sets a target shift after a predetermined time based on the accelerator opening, the vehicle speed, and the running resistance. A stage is set. That is, as shown in FIG. 4, the vehicle is provided with a running resistance detection sensor 41 that detects the running resistance of the vehicle, and outputs the detected running resistance of the vehicle to the ECU 21.

  The traveling resistance includes road gradient, vehicle weight, longitudinal acceleration, lateral acceleration, and the like. Examples of the running resistance detection sensor 41 include a car navigation system, a suspension system (stroke sensor), a load sensor, a seat belt sensor, and an acceleration sensor. The ECU 21 includes map (gradient) information from the car navigation system, vehicle weight from the suspension system (stroke sensor), vehicle weight from the load sensor, occupant (vehicle weight) information from the seat belt sensor, driving force and vehicle speed. The running resistance is calculated by taking in the longitudinal acceleration information from the change and the longitudinal acceleration and lateral acceleration information from the acceleration sensor.

  Here, kick-down control by the control device for the automatic transmission according to the second embodiment will be described with reference to the flowchart of FIG.

  In the kickdown control by the automatic transmission control device of the second embodiment, as shown in FIG. 5, in step S21, the ECU 21 determines whether or not there is a kickdown determination by the normal shift control. Here, it is determined whether or not a kick-down operation by the driver is detected based on the change amount of the accelerator opening. Here, when the kick down operation is not detected, the routine exits without doing anything.

  On the other hand, if a kick-down operation is detected in step S21, the vehicle acceleration is calculated from the accelerator opening, the current vehicle speed, and the running resistance in step S22, and is set in advance after the kick-down operation is detected. The vehicle speed after the elapse of the predetermined time T1 is estimated. Subsequently, in step S23, a shift determination is performed from the vehicle speed after the elapse of the predetermined time T1 and the current accelerator opening, and the target gear position after the elapse of the predetermined time T1 is estimated.

  In step S24, the ECU 21 compares the current gear stage g0 with the target gear stage g2, and when the target gear stage g2 is at a lower speed side than the current gear stage g0, the ECU 21 proceeds to step S25, where the throttle opening is performed. The gear stage g1 is set based on the speed and the vehicle speed, and downshifting to this gear stage g1 is executed. On the other hand, when the target gear stage g2 is the same as the current gear stage g0 in step S24, downshifting is prohibited in step S26.

  As described above, in the control device for the automatic transmission according to the second embodiment, when a kickdown operation by the driver is detected, a predetermined time elapses from the kickdown operation based on the accelerator opening, the vehicle speed, and the running resistance. When a later target shift speed is set and the target shift speed is lower than the current shift speed, a downshift is executed based on the throttle opening and the vehicle speed, while the target shift speed is the same as the current shift speed. In some cases, downshifting is prohibited.

  Therefore, if the target shift speed is lower than the current shift speed, the shift down is permitted. On the other hand, if the target shift speed is the same as the current shift speed, the shift down is prohibited, thereby preventing the busy shift phenomenon. Occurrence can be prevented and appropriate kickdown control can be performed, drivability can be improved, and fuel consumption can be improved by suppressing frequent shifts.

  In the control device for an automatic transmission according to the second embodiment, a running resistance detection sensor 41 that detects the running resistance of the vehicle is provided, and the ECU 21 sets the target shift after a predetermined time based on the accelerator opening, the vehicle speed, and the running resistance. A stage is set. Therefore, regardless of the traveling environment of the vehicle, the target shift speed can be calculated with high accuracy, and the controllability of kick-down control can be improved.

  In each of the above-described embodiments, the downshift is prohibited when the target shift speed after the predetermined time has elapsed is the same as the current shift speed. However, the target shift speed after the predetermined time has elapsed is less than the current shift speed. Even on the high speed side, downshifting is prohibited. Further, when the target shift speed after the predetermined time has elapsed is the same as the current shift speed or on the high speed side, the shift down is prohibited, but the target shift speed after the predetermined time has elapsed is the same as the current shift speed or When it is on the high speed side, the shift down is suppressed, that is, when the shift down is the second speed or higher, the shift down of only the first speed may be permitted.

  As described above, when the kickdown operation is performed, the control device for the automatic transmission according to the present invention, when the target shift speed after a predetermined time has elapsed is the same as the current shift speed or on the high speed side, By suppressing or prohibiting downshifting, appropriate kickdown control can be performed to improve drivability and improve fuel efficiency, which is useful for any internal combustion engine.

It is a schematic block diagram showing the control apparatus of the automatic transmission which concerns on Example 1 of this invention. 3 is a flowchart illustrating kickdown control by the control device for the automatic transmission according to the first embodiment. 3 is a time chart illustrating kick down control by the automatic transmission control device according to the first embodiment. 3 is a time chart illustrating kick down control by the automatic transmission control device according to the first embodiment. It is a schematic block diagram showing the control apparatus of the automatic transmission which concerns on Example 2 of this invention. 7 is a flowchart showing kickdown control by the automatic transmission control apparatus according to the second embodiment.

Explanation of symbols

11 Engine (Internal combustion engine)
12 Torque converter 13 Transmission 14 Automatic transmission 21 Electronic control unit, ECU (Kickdown operation detection means, kickdown control execution means, target gear position setting means, kickdown control suppression prohibition means)
23 Throttle position sensor 24 Accelerator position sensor 33 Vehicle speed sensor 41 Running resistance detection sensor

Claims (5)

In a control device for an automatic transmission that shifts and outputs a driving force of an internal combustion engine,
Kick-down operation detecting means for detecting a kick-down operation by the driver;
Kick down control execution means for performing a downshift based on the throttle opening and the vehicle speed when a kickdown operation is detected;
A target gear position setting means for setting a target gear position after a predetermined time has elapsed from the kick-down operation based on the accelerator opening and the vehicle speed when a kick-down operation is detected;
Kick down control suppression prohibiting means for suppressing or prohibiting shift down when the target shift speed is the same as or higher than the current shift speed;
A control device for an automatic transmission, comprising:   2. The control apparatus for an automatic transmission according to claim 1, wherein the predetermined time is set in consideration of a busy shift feeling of a driver with a time required for downshifting.   The control apparatus for an automatic transmission according to claim 1 or 2, wherein the predetermined time is set in accordance with a shift speed, a shift mode, and a vehicle speed accelerator opening.   The target gear position setting means estimates a target vehicle speed after a predetermined time has elapsed based on the current accelerator opening and the current vehicle speed, and sets the target gear speed based on the target vehicle speed and the current accelerator opening. The control apparatus for an automatic transmission according to any one of claims 1 to 3.   A running resistance detecting means for detecting a running resistance of the vehicle is provided, and the target shift speed setting means sets a target shift speed after a predetermined time based on an accelerator opening, a vehicle speed, and a running resistance. Item 5. The automatic transmission control device according to Item 4.

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