JP2010210042A - Shift control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shift control device enhancing drivability by restricting lowering of the driving torque due to up-shift. <P>SOLUTION: This shift control device includes: an engine speed detecting means for detecting the engine speed before up-shift by an automatic transmission 32; an engine speed estimating means for estimating the engine speed after the up-shift by the automatic transmission 32; and an up-shift determining means for determining permission and prohibition of the up-shift by the automatic transmission 32 based on the real engine speed before the up-shift, the estimated engine speed after the up-shift and the maximum engine torque corresponding to the engine speed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a speed change control device, and more particularly to control for determining whether an upshift is permitted or prohibited in accordance with a supercharging pressure in an internal combustion engine with a supercharger.

  In a shift control device for an automatic transmission connected to an internal combustion engine, in general, an accelerator opening (or a throttle opening) corresponding to a depression operation of an accelerator pedal by a driver and a current vehicle speed are determined. A target driving force is set, and the engine speed and the gear position are set based on the target driving force. An upshift region is set in the shift control device of the automatic transmission. That is, when the driver depresses the accelerator pedal and the vehicle is accelerating, the upshift control is executed according to the increase in the vehicle speed.

  An example of such a shift control device for an automatic transmission is disclosed in Patent Document 1 below. In the powertrain control device described in Patent Document 1, the upshift prohibition condition is changed according to the supercharging state by the supercharger. Specifically, when the difference between the standard torque based on the throttle opening and the engine speed and the actual torque based on the intake air amount and the engine speed is larger than a predetermined value, the boost pressure increases. It is presumed that it has not, and upshifts are prohibited.

JP 2006-177488 A

  In the conventional powertrain control device described above, upshifting is prohibited when the supercharged state by the supercharger is not sufficient. As a criterion for determining whether the supercharged state by the supercharger is sufficient, the difference between the standard torque based on the throttle opening and the engine speed and the actual torque based on the intake air amount and the engine speed That is, the increase / decrease delay of the intake air amount (supercharging pressure) is used.

  However, even if the supercharged state by the supercharger is sufficient, the engine speed decreases when the transmission is upshifted, and the area where the exhaust gas is low, such as the low engine speed range, makes it difficult to supercharge Then, after the upshift, the engine torque may decrease and the drivability may deteriorate.

  An object of the present invention is to solve such a problem, and an object of the present invention is to provide a speed change control device capable of improving drivability by suppressing a decrease in driving torque due to an upshift.

  In order to solve the above-described problems and achieve the object, a shift control apparatus according to the present invention is a shift control apparatus that controls an automatic transmission capable of shifting and outputting the rotational speed of an internal combustion engine having a supercharger. A rotation speed detecting means for detecting the rotation speed of the internal combustion engine before the upshift by the automatic transmission; a rotation speed estimation means for estimating the rotation speed of the internal combustion engine after the upshift by the automatic transmission; Upshift determination means for determining whether or not to allow upshifting by the automatic transmission based on the previous actual rotational speed, the estimated rotational speed after the upshift, and the engine maximum torque corresponding to the rotational speed of the internal combustion engine; It is characterized by providing.

  In the shift control device of the present invention, a transmission input shaft rotational speed detection means for detecting a transmission input shaft rotational speed input from the internal combustion engine to the automatic transmission, and between the internal combustion engine and the automatic transmission. A slip amount detecting means for detecting a slip amount of a torque converter provided, wherein the rotational speed estimating means is configured to upshift based on a transmission input shaft rotational speed before the upshift and a gear ratio changed by the upshift. The post-transmission input shaft rotational speed is calculated, and the estimated rotational speed after the upshift is estimated by adding the slip amount to the post-upshift transmission input shaft rotational speed.

  In the shift control device of the present invention, the pre-shift driving torque is calculated based on the supercharging pressure detecting means for detecting the supercharging pressure of the supercharger, the actual rotational speed before the upshift and the supercharging pressure. Drive torque calculating means, and post-shift drive torque calculating means for calculating a post-shift drive torque maximum value based on the estimated rotation speed after upshift and the engine maximum torque are provided, and the upshift determining means is pre-shift drive When the deviation between the torque and the maximum drive torque after shifting is equal to or greater than a predetermined value set in advance, the upshift by the automatic transmission is prohibited.

  According to the speed change control device of the present invention, it depends on the actual rotational speed of the internal combustion engine before the upshift by the automatic transmission, the estimated rotational speed of the internal combustion engine after the upshift by the automatic transmission, and the rotational speed of the internal combustion engine. The upshift by the automatic transmission is prohibited based on the engine maximum torque. Accordingly, it is possible to improve drivability by suppressing a decrease in driving torque due to an upshift.

FIG. 1 is a schematic configuration diagram showing a shift control apparatus according to an embodiment of the present invention. FIG. 2 is a flowchart showing the upshift control in the shift control apparatus of this embodiment. FIG. 3 is a graph showing engine torque with respect to engine speed by upshift control.

  Embodiments of a shift control apparatus 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.

  FIG. 1 is a schematic configuration diagram showing a shift control device according to an embodiment of the present invention, FIG. 2 is a flowchart showing upshift control in the shift control device of this embodiment, and FIG. 3 is an engine rotation by upshift control. It is a graph showing the engine torque with respect to a number.

  In the transmission control apparatus of the present embodiment, as shown in FIG. 1, an engine 11 as an internal combustion engine is configured by a cylinder head being fastened on a cylinder block, and a plurality of cylinders are arranged, although not shown. A piston is fitted to each cylinder so as to be movable up and down, and each piston is connected to a crankshaft via a connecting rod.

  An intake manifold 12 is connected to a combustion chamber (cylinder) of the engine 11 via an intake port, and an intake pipe 14 is connected to the intake manifold 12 via a surge tank 13. The intake pipe 14 is provided with an air cleaner 15 at the air intake, and an electronic throttle device 16 having a throttle valve is provided on the downstream side of the air cleaner 15.

  An exhaust manifold 17 is connected to the combustion chamber (cylinder) of the engine 11 via an exhaust port, and an exhaust pipe 18 is connected to the exhaust manifold 17. A three-way catalyst 19 is connected to the exhaust pipe 18. , 20 are installed.

  A turbocharger 21 is provided in the intake pipe 14 and the exhaust pipe 18. The turbocharger 21 is formed by integrally connecting a compressor 21a provided in the intake pipe 14 and a turbine 21b provided in the exhaust pipe 18 by a drive shaft 21c. An intercooler 22 is provided in the intake pipe 14 on the downstream side of the compressor 21a in the turbocharger 21 to cool the intake air that has been supercharged by the compressor 21a and whose temperature has risen.

  In addition, an injector that injects fuel into the intake port or the combustion chamber is mounted inside the engine 11 and a spark plug that ignites the air-fuel mixture in the combustion chamber is mounted.

  An engine control unit (ECU) 23 is mounted on the vehicle, and the ECU 23 can control the fuel injection amount and injection timing by the injector, the ignition timing by the spark plug, and the like. The fuel injection amount, injection timing, ignition timing, etc. are determined based on the engine operating state such as the throttle opening and the engine speed.

  That is, an air flow sensor 24 is mounted on the upstream side of the intake pipe 14 and outputs the measured intake air amount to the ECU 23. The electronic throttle device 16 is provided with a throttle position sensor 25 and outputs the current throttle opening to the ECU 23. The crankshaft is provided with a crank angle sensor 26, which outputs the detected crank angle to the ECU 23. The ECU 23 calculates the engine speed based on the crank angle. The surge tank 13 is provided with a supercharging pressure sensor 27 that detects the supercharging pressure of the intake air supercharged by the turbocharger 21 (compressor 21 a), and outputs the detected supercharging pressure to the ECU 23. Further, an accelerator opening sensor 28 that detects an accelerator opening according to the amount of depression of the accelerator pedal is provided, and the detected accelerator opening is output to the ECU 23.

  A stepped automatic transmission 32 is connected to the engine 11 thus configured via a torque converter 31. In the automatic transmission 32, a propeller shaft 33 is connected to the output side, left and right drive shafts 35 are connected to the propeller shaft 33 via a differential gear 34, and left and right drive wheels 36 are connected to the drive shaft 35. Has been.

  Therefore, when the engine 11 is driven, the driving force is output from the crankshaft and input to the input shaft of the automatic transmission 32 via the torque converter 31, 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 32 to the propeller shaft 33 and is transmitted from the propeller shaft 33 to the left and right drive shafts 35 via the differential gear 34 to drive the left and right drive wheels 36. Can rotate.

  The automatic transmission 32 is hydraulically controlled by a hydraulic control device 37. The ECU 23 described above can control the shift timing and the like by controlling the hydraulic control device 37 and hydraulically controlling the automatic transmission 32. That is, the automatic transmission 32 is provided with an input shaft rotational speed sensor 38 that detects the input shaft rotational speed, and outputs the detected input shaft rotational speed to the ECU 23. The shift lever device operated by the driver is provided with a shift sensor 39 that detects an operation position, that is, parking (P), reverse (R), neutral (N), and drive (D), and detects the detected operation signal. It is output to the ECU 23. The vehicle is provided with a vehicle speed sensor 40 that detects the speed, and outputs the detected vehicle speed to the ECU 23.

  Therefore, the ECU 23 controls the shift of the automatic transmission 32 according to the amount of depression of the accelerator pedal (accelerator opening) by the driver and the vehicle speed when the shift lever 39 is operated by the shift sensor 39 in the drive (D). Is controlling.

  In this case, the ECU 23 executes shift control by the automatic transmission 32 based on a preset shift map (shift line). In this shift map, for example, the vertical axis is the accelerator opening, and the horizontal axis is the vehicle speed, and the accelerator opening and the vehicle speed as the running state of the vehicle, and the target value of the shift stage of the automatic transmission 32. It defines the correspondence with the target gear stage. In other words, the ECU 23 sets up a plurality of shift speeds according to the accelerator opening and the vehicle speed, and executes upshift control and downshift control.

  In the shift control device of this embodiment, the rotation speed detecting means for detecting the rotation speed of the engine 11 before the upshift by the automatic transmission 32 and the rotation speed of the engine 11 after the upshift by the automatic transmission 32 are estimated. To determine whether or not to allow upshifting by the automatic transmission based on the rotational speed estimation means to perform, the actual rotational speed before the upshift, the estimated rotational speed after the upshift, and the engine maximum torque according to the engine speed Shift determination means.

  In this embodiment, the ECU 23 and the crank angle sensor 26 function as the rotational speed detection means, the ECU 23 functions as the rotational speed estimation means, and the ECU 23 functions as the upshift determination means. The engine maximum torque corresponding to the engine speed is a design value of the engine 11 and is set in advance.

  In this case, a slip of the transmission input shaft rotational speed detection means for detecting the transmission input shaft rotational speed input from the engine 11 to the automatic transmission 32 and the torque converter 31 provided between the engine 11 and the automatic transmission 32. A slip amount detecting means for detecting the amount, and the ECU 23 as the rotational speed estimating means is a transmission after the upshift based on the transmission input shaft rotational speed before the upshift and the gear ratio changed by the upshift. The estimated rotational speed after the upshift is estimated by calculating the input shaft rotational speed and adding the slip amount to the transmission input shaft rotational speed after the upshift.

  In this embodiment, the input shaft rotational speed sensor 38 functions as the transmission input shaft rotational speed detection means. The slip amount detection means sets a different slip amount according to the operating state of the torque converter 31. That is, since the torque converter 31 has a lock-up mechanism, the amount of slip differs when the lock-up is ON, when the flex lock-up is performed, and when the lock-up is OFF. When the lockup is ON, the crankshaft of the engine 11 and the input shaft of the automatic transmission 32 are directly connected, so the slip amount becomes zero. At the time of flex lockup, the torque converter 31 (lockup clutch) is slid at a predetermined rotational speed and used, so the slip amount becomes a set value. When the lock-up is OFF, the torque converter 31 (lock-up clutch) is slid according to the running state of the vehicle. Therefore, the slip amount is determined by a map with an initial value of 0. In this map, the slip amount is set according to the accelerator opening and the transmission input shaft rotation speed, and data is accumulated by learning control.

  Further, in the shift control device of the present embodiment, the pre-shift driving torque is calculated based on the supercharging pressure detecting means for detecting the supercharging pressure of the turbocharger 21, the actual rotational speed before the upshift, and the supercharging pressure. Pre-shift driving torque calculating means for calculating, and post-shift driving torque calculating means for calculating a post-shift driving torque maximum value based on the estimated rotational speed and engine maximum torque after the upshift are provided, and as an upshift determining means The ECU 23 prohibits the upshift by the automatic transmission 32 when the deviation between the pre-shift driving torque and the post-shift driving torque maximum value is equal to or greater than a predetermined value set in advance.

  In this case, the supercharging pressure sensor 27 functions as the supercharging pressure detection means, and the ECU 23 functions as the driving torque calculation means before shifting and the driving torque calculation means after shifting.

  Here, the upshift control in the shift control apparatus of the present embodiment will be described in detail based on the flowchart of FIG.

  In the upshift control in the speed change control apparatus of this embodiment, as shown in FIG. 2, in step S11, the ECU 23 reads the vehicle speed and the accelerator opening, and in step S12, determines the upshift. The determination of the upshift is performed by using the above-described shift map (vehicle speed-accelerator opening-shift stage) to determine whether an upshift is necessary. If it is determined that an upshift is not necessary, the routine exits without doing anything.

  On the other hand, if it is determined in step S12 that an upshift is necessary, in step S13, the ECU 23 determines whether or not the amount of change in the accelerator opening is 0 or more. Here, if it is determined that the amount of change in the accelerator opening is not greater than or equal to 0, this routine is exited without doing anything. On the other hand, if it is determined that the amount of change in the accelerator opening is 0 or more, the process proceeds to step S14.

  In step S14, the ECU 23 reads the current engine speed (actual speed) and the current supercharging pressure before the upshift (shift), and in step S15, the engine speed after the upshift (shift). The number (estimated rotational speed) is calculated. In this case, the ECU 23 calculates the transmission input shaft rotational speed after the upshift based on the transmission input shaft rotational speed before the upshift and the gear ratio changed by the upshift, and the transmission input after the upshift. By adding the slip amount to the shaft speed, the engine speed (estimated speed) after the upshift (shift) is calculated. It is set according to the slip amount and the operating state of the torque converter 31.

  In step S16, the engine torque before the upshift (shift) and the maximum engine torque after the upshift (shift) are calculated. In this case, drive torque before upshift (shift) is calculated based on the engine speed and boost pressure before upshift. Further, a drive torque after upshift (shift) is calculated based on the engine speed after the upshift and the engine maximum torque. In this case, the maximum torque corresponding to the rotational speed is set based on the design value of the engine 11, and the ECU 23 stores this as a map, for example.

  In step S17, the ECU 23 determines whether or not a deviation (difference) between the pre-upshift drive torque and the post-upshift drive torque maximum value is smaller than a predetermined value a set in advance. Here, if it is determined that the deviation between the pre-upshift driving torque and the post-upshift driving torque maximum value is smaller than the predetermined value a, the reduction in the driving torque after the upshift is not large, so in step S18, the automatic transmission Allow upshift by 32. On the other hand, if it is determined that the deviation between the pre-upshift driving torque and the post-upshift driving torque maximum value is equal to or greater than the predetermined value a, the reduction in the driving torque after the upshift is large, so in step S19, the automatic transmission 32. The upshift by is prohibited.

  That is, when the maximum drive torque value after the upshift is not so low with respect to the drive torque before the upshift, even if the upshift by the automatic transmission 32 is performed, the torque fluctuation of the vehicle is small, so this upshift is permitted. . On the other hand, when the post-upshift drive torque is lower than the pre-upshift drive torque, if the upshift by the automatic transmission 32 is executed, the vehicle torque fluctuation is large, and this upshift is prohibited.

  The engine torque (Nm) with respect to the engine speed (rpm) by the upshift control in FIG. 3 will be described in detail. In the graph of FIG. 3, the horizontal axis represents the engine speed, the vertical axis represents the engine torque, the maximum engine torque (engine maximum torque) is set, and the region of the engine torque that can be exhibited by the engine 11 is the boost pressure− It is partitioned according to 40-80 kPa.

  As can be seen from this graph, when the post-upshift drive torque maximum value T2 (Δ) is estimated with respect to the pre-upshift drive torque T1 (□), the engine speed decreases and the boost pressure increases after the upshift. And the maximum engine torque after the upshift T2 (Δ) is reduced, and in this case, the upshift is prohibited.

  On the other hand, when the post-upshift driving torque maximum value T4 (◯) is estimated with respect to the pre-upshift driving torque T3 (□), the engine pressure decreases but the supercharging pressure decreases after the upshift. Since the maximum engine torque is sufficiently high, the post-upshift drive torque maximum value T4 (O) does not decrease, and in this case, the upshift is permitted. Note that the post-upshift drive torque maximum value T4 (◯) depends on the maximum engine torque, so that the supercharging pressure exceeds 80. Actually, the post-upshift drive torque is the accelerator opening after the upshift. Since it depends on (throttle opening), it becomes the driving torque T5 (◯) after the upshift.

  As described above, the shift control apparatus according to this embodiment is configured to control the automatic transmission 32 that can output by changing the rotational speed of the engine 11 having the turbocharger 21. , An engine speed detecting means for detecting the engine speed before the upshift, an engine speed estimating means for estimating the engine speed after the upshift by the automatic transmission 32, the actual speed before the upshift and the speed after the upshift. Upshift determination means is provided for determining whether the automatic transmission 32 is permitted or prohibited from upshifting based on the estimated rotational speed and the engine maximum torque corresponding to the engine rotational speed.

  Therefore, since the engine torque is defined by the engine maximum torque, the torque fluctuation after the upshift is estimated based on the engine speed before and after the upshift and the engine maximum torque. Therefore, it is possible to appropriately determine whether or not to allow upshifting, and it is possible to improve drivability by suppressing a decrease in driving torque due to upshifting.

  Further, in the driving force control apparatus of the present embodiment, the transmission input shaft rotational speed after the upshift is calculated based on the transmission input shaft rotational speed before the upshift and the gear ratio changed by the upshift. The estimated rotational speed after upshifting is estimated by adding the slip amount to the transmission input shaft rotational speed after the shift. Therefore, the estimated rotational speed after the upshift can be detected with high accuracy.

  Further, in the driving force control apparatus of the present embodiment, the pre-shift driving torque is calculated based on the actual rotational speed before the upshift and the boost pressure, and based on the estimated rotational speed after the upshift and the engine maximum torque. The maximum drive torque value after the shift is calculated, and when the deviation between the drive torque before the shift and the maximum drive torque value after the shift is greater than or equal to a predetermined value set in advance, the upshift by the automatic transmission 32 is prohibited. Therefore, when it is estimated that the driving torque after the upshift is reduced, the upshift is prohibited, so that the reduction in the driving torque due to the upshift can be suppressed and the drivability can be improved.

  In the above-described embodiment, the pre-shift driving torque is calculated based on the engine speed before the upshift and the supercharging pressure. May be. In addition, the maximum drive torque after shifting was calculated based on the engine speed and engine maximum torque after the upshift, but in addition to the engine speed and engine maximum torque after the upshift, the throttle opening was added to change the speed. The maximum value of the rear drive torque may be calculated.

  As described above, the speed change control device according to the present invention determines whether to permit or prohibit the upshift based on the actual rotational speed before the upshift, the estimated rotational speed after the upshift, and the engine maximum torque. It is possible to improve the drivability by suppressing the decrease of the driving torque due to the shift, and it is useful when applied to any vehicle.

11 Engine (Internal combustion engine)
21 Turbocharger 23 Electronic control unit, ECU (rotation speed detection means, rotation speed estimation means, upshift determination means, slip amount detection means, pre-shift drive torque calculation means, post-shift drive torque calculation means)
26 Crank angle sensor (rotational speed detection means)
27 Supercharging pressure sensor (Supercharging pressure detection means)
31 Torque converter 32 Automatic transmission 37 Hydraulic control device 38 Input shaft rotational speed sensor (transmission input shaft rotational speed detection means)

Claims (3)

In a shift control device for controlling an automatic transmission capable of shifting and outputting the rotational speed of an internal combustion engine having a supercharger,
A rotational speed detection means for detecting the rotational speed of the internal combustion engine before the upshift by the automatic transmission;
A rotational speed estimating means for estimating the rotational speed of the internal combustion engine after the upshift by the automatic transmission;
Upshift determination means for determining whether the automatic transmission is permitted or prohibited by the automatic transmission based on the actual rotational speed before the upshift, the estimated rotational speed after the upshift, and the engine maximum torque corresponding to the rotational speed of the internal combustion engine. When,
A shift control apparatus comprising: A transmission input shaft rotational speed detection means for detecting a transmission input shaft rotational speed input from the internal combustion engine to the automatic transmission, and a slip amount of a torque converter provided between the internal combustion engine and the automatic transmission. Slip amount detecting means for detecting,
The rotational speed estimation means calculates the transmission input shaft rotational speed after the upshift based on the transmission input shaft rotational speed before the upshift and the gear ratio changed by the upshift, and the transmission after the upshift. A shift control apparatus that estimates an estimated rotational speed after an upshift by adding a slip amount to an input shaft rotational speed. A supercharging pressure detecting means for detecting a supercharging pressure of the supercharger; a pre-shift driving torque calculating means for calculating a pre-shift driving torque based on an actual rotational speed and a supercharging pressure before the upshift; and an upshift A post-shift drive torque calculating means for calculating a post-shift drive torque maximum value based on the subsequent estimated rotational speed and the engine maximum torque;
The upshift determination unit prohibits an upshift by the automatic transmission when a deviation between a pre-shift driving torque and a post-shift driving torque maximum value is equal to or greater than a predetermined value. 3. A transmission control device according to 1 or 2.

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