JP5525430B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine used in a vehicle with an automatic transmission having a torque converter having a lock-up clutch.

  Conventionally, a control technique of an internal combustion engine for smoothly accelerating a vehicle has been disclosed. For example, Patent Document 1 discloses a fuel control device for a vehicle engine with an automatic transmission. In this apparatus, in order to accelerate the vehicle smoothly, the slip rate of the torque converter is calculated, and control is performed to change the fuel increase amount according to the obtained slip rate.

JP 63-268946 A

  However, the slip rate used in the control according to Patent Document 1 is a value obtained after the throttle valve is opened during acceleration of the vehicle and the operating pressure of the lockup clutch is changed. Engine control will be delayed. As a result, in the control according to Patent Document 1, there is a case where the vehicle cannot be accelerated smoothly.

  Therefore, an object of the present invention is to provide a control device for an internal combustion engine that can smoothly accelerate the vehicle without delaying the control of the internal combustion engine with respect to the operation of the lockup clutch.

  The present invention is used in a vehicle with an automatic transmission having an internal combustion engine and a torque converter having a lock-up clutch, and at the time of acceleration of the vehicle accompanying an accelerator operation, the target output of the internal combustion engine accompanying the accelerator operation is It is a control device for an internal combustion engine provided with a restricting means for restricting an engine output change amount to a predetermined speed. The restricting means sets a predetermined speed based on the target operating pressure of the lockup clutch at the time of acceleration and the actual measured value or target value of the lockup clutch immediately before acceleration or the control state of the lockup clutch. It has a regulation value setting means.

  According to the present invention, by considering the target operating pressure of the lockup clutch, the output change amount of the internal combustion engine can be controlled without causing a delay with respect to the operation of the lockup clutch. In addition, according to the present invention, the output change amount of the internal combustion engine can be appropriately controlled with respect to the operation of the lockup clutch by considering the state of the lockup clutch immediately before the acceleration of the vehicle.

  According to one aspect of the present invention, the internal combustion engine includes a throttle valve that controls the intake air amount, the restricting means restricts the target opening of the throttle valve, and the restriction value setting means sets an allowable change amount of the target opening. .

  According to one aspect of the present invention, torque shock and vibration during vehicle acceleration can be avoided by controlling the throttle valve in accordance with the engagement state of the lockup clutch.

  According to an aspect of the present invention, in the state where the automatic transmission temporarily increases the target operating pressure of the lock-up clutch to a predetermined value as the vehicle accelerates, the regulation value is set. The means sets a regulation value (predetermined speed or target opening of the throttle valve) assuming that the target operating pressure is held at the predetermined value.

  According to one aspect of the present invention, the target operating pressure is temporarily reduced during acceleration of the vehicle, so that the operation noise of the automatic transmission can be reduced and the temporary decrease in the target operating pressure is ignored and regulated. By setting the value (predetermined speed or target opening of the throttle valve), a sudden change in the output of the internal combustion engine can be avoided.

It is a figure which shows roughly the control apparatus by embodiment of this invention with the internal combustion engine to which this is applied. It is a block diagram of control of the throttle opening by embodiment of this invention. It is a figure which shows the mode of control of the request | required torque or the target throttle opening by embodiment of this invention. It is a figure which shows the control flow for the correction amount calculation of the request torque or target throttle opening by embodiment of this invention. It is a figure which shows the time change of the operating pressure (LC pressure) of the lockup clutch by embodiment of this invention. It is a figure which shows the time change of (a) AP opening degree which is a control object by embodiment of this invention, (b) LC pressure, and (c) target throttle (TH) opening degree. It is a figure which shows the relationship between the target LC pressure and correction | amendment gain by embodiment of this invention. It is a figure which shows the control flow of the incremental correction | amendment according to LC pressure by embodiment of this invention. It is a figure which shows the time change (b), such as the time change (a) of LC pressure and target throttle (TH) opening degree by embodiment of this invention. It is a figure which shows the time change (a) of LC pressure and the time change (b) of target TH opening by embodiment of this invention. It is a figure which shows the relationship between the present LC pressure and correction | amendment gain by embodiment of this invention. It is a figure which shows the control flow of the incremental correction | amendment according to LC control mode by embodiment of this invention. It is a figure which shows the time change (a) of LC control mode and the time change (b) of target TH opening by embodiment of this invention. It is a figure which shows the time change (a) of LC control mode and the time change (b) of target TH opening by embodiment of this invention. It is a figure which shows the relationship between the present LC pressure and correction | amendment gain by embodiment of this invention. It is a figure which shows the control flow of the incremental correction | amendment according to the difference of LC pressure during deceleration and LC pressure during acceleration by embodiment of this invention. It is a figure which shows the time change (a) of the difference of LC pressure by the embodiment of this invention, and the time change (b) of target TH opening.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 schematically shows a control apparatus 1 for an internal combustion engine according to the present embodiment, together with an internal combustion engine 3 (hereinafter referred to as “engine”) to which the control apparatus 1 is applied. The engine 3 is a 4-cylinder 4-cycle engine mounted on the vehicle V, for example.

  The electronic control unit (hereinafter referred to as “ECU”) 2 is a computer including an input / output interface, a central processing unit (CPU), and a memory. The memory can store a computer program for realizing various controls of the vehicle and data necessary for executing the program. A program for control according to the present invention, and data and a map used when executing the program are stored in a memory. The ECU 2 receives data sent from each part of the vehicle, performs calculation, generates a control signal, and sends it to control each part of the engine 3.

  Each cylinder (not shown) of the engine 3 is provided with an injector 4 (only one is shown). The injector 4 injects fuel supplied from a fuel supply device (not shown) into the cylinder. The fuel injection amount of the injector 4 is controlled by a drive signal from the ECU 2 described later.

  The crankshaft 10 of the engine 3 is provided with a crank angle sensor 21 composed of, for example, a magnet rotor and an MRE pickup. The crank angle sensor 21 outputs a CRK signal and a TDC signal, which are both pulse signals, to the ECU 2 as the crankshaft 10 rotates. The CRK signal is output every predetermined crank angle (for example, 10 degrees). The ECU 2 calculates the rotational speed NE of the engine 3 based on this CRK signal. The TDC signal is a signal indicating that, in each cylinder of the engine 3, a piston (not shown) is at a predetermined crank angle position slightly before top dead center at the start of the intake stroke. In the case of such a 4-cylinder engine, it is output every 180 degrees of crank angle.

  The vehicle V is of a front engine / front drive type, and the engine 3 has left and right front wheels W (drive wheels) via an automatic transmission 9, a final reduction gear (not shown), a drive shaft 12, and the like. Only one is shown).

  The automatic transmission 9 is a combination of a torque converter 6 with a lock-up clutch 7 and a stepped transmission 8. The lock-up clutch 7 is connected and disconnected by the supply of hydraulic pressure from the hydraulic circuit 5. The The type of the automatic transmission 9 is not limited to a stepped transmission, and may be a continuously variable transmission, a double clutch transmission, or the like. The hydraulic circuit 5 is provided with an LC electromagnetic valve 5a and a hydraulic sensor 5b, both of which are electrically connected to the ECU 2. By controlling the operation state of the LC solenoid valve 5a by the ECU 2, the connection / disconnection state of the lock-up clutch 7 is controlled. In this case, when the lockup clutch 7 is completely connected (engaged), the crankshaft 10 of the engine 3 is mechanically directly connected to the driven shaft 11 of the torque converter 6. The hydraulic pressure sensor 5b sends the detected hydraulic pressure (LC pressure) signal to the ECU 2.

  A rotation speed sensor 23 is provided on the driven shaft 11. Similar to the crank angle sensor 21, the rotational speed sensor 23 includes a magnet rotor and an MRE pickup, and outputs a detection signal that is a pulse signal to the ECU 2 every time the driven shaft 11 rotates by a predetermined angle. The ECU 2 calculates the rotational speed of the driven shaft 11 based on this detection signal.

  A detection signal representing an operation amount (hereinafter referred to as “accelerator opening”) AP of an accelerator pedal (not shown) is output from the accelerator opening sensor 22 to the ECU 2.

  A throttle valve 14 is disposed in the intake pipe 13. The throttle valve 14 is a drive-by-wire (DBW) type throttle valve that is driven by an actuator (not shown) in accordance with a control signal from the ECU 2. A throttle valve opening sensor 24 is provided in the throttle valve 14 and outputs a signal corresponding to the throttle opening to the ECU 2.

  Next, control of the throttle opening during vehicle acceleration according to the present embodiment will be described. FIG. 2 is a block diagram of the throttle opening degree control executed by the control device 1 of FIG. First, in block 32, the required torque of the engine 3 (hereinafter referred to as “request TRQ”) or the target throttle opening (hereinafter referred to as “target TH”) is determined from the accelerator opening (AP) 30 and the engine speed (NE) 31. Opening ”) is calculated. In block 33, a filtering process is performed on the obtained request TRQ or target TH opening.

  This filtering process is performed as follows, for example. FIG. 3 is a diagram illustrating how the required TRQ or the target TH opening is controlled. FIG. 3 shows a pulse 41 that rises in a stepwise manner after the filtering process with respect to a set pulse (temporal change) 40 of the required TRQ or target TH opening. As described above, the filtering process according to the present embodiment means a process for gradually increasing the request TRQ or the target TH opening, rather than increasing the required TRQ or the target TH opening gradually (slowing the rise of the signal).

In the filtering process of FIG. 3, the required TRQ or target TH opening is increased by ΔTRQ or ΔTH every Δt time. This Δt time is, for example, 10 ms. The increase ΔTRQ or ΔTH is calculated as an incremental correction amount of the required TRQ or the target TH opening in the block 34 of FIG. Details of the control for calculating the incremental correction amount will be described later. Finally, in block 35 of FIG. 2, the opening (θ _TH ) of the throttle valve 14 is calculated based on the request TRQ or the target TH opening after the filtering process.

  FIG. 4 is a diagram showing a control flow for calculating an incremental correction amount of the required TRQ or the target TH opening. The control flow in FIG. 4 is executed by the ECU 2 of the control device 1 at a predetermined cycle. In step S1, it is determined whether or not the accelerator pedal is depressed. This determination is performed to confirm whether or not the vehicle is accelerating. Specifically, for example, it is determined whether or not the accelerator opening (AP) is a predetermined value or more. When this determination is No, in step S3, the lockup clutch operating pressure (hereinafter referred to as "LC pressure") and the lockup clutch control mode (hereinafter referred to as "LC control mode") are turned on or off (clutch lockup). (Or the cancellation thereof) is monitored, and then this control is terminated.

  If the determination in step S1 is Yes, in the next step S2, it is determined whether or not the LC control mode is off. When this determination is Yes, the LC pressure hold processing for cornflower is performed in step S4. Here, the dongle means a state in which smooth acceleration is prevented because the vehicle vibrates due to large fluctuations in the output torque of the engine during acceleration of the vehicle.

  With reference to FIG. 5, the LC pressure hold processing for cornflower will be described. FIG. 5 is a diagram showing the time change of the LC pressure. In FIG. 5, it is assumed that the vehicle is switched from the deceleration mode to the acceleration mode at time T1. At time T1, the LC control mode is turned on, that is, the clutch is locked up, and the target LC pressure is raised in a pulse shape as indicated by reference numeral 43. When the LC control mode is turned off at time T2, the target LC pressure is reduced to a predetermined value (for example, zero), and control for rapidly decreasing the LC pressure is executed. Thereafter, when the LC control mode is turned on at time T3, the target LC pressure is returned to the predetermined value again.

  As described above, when the target LC pressure changes rapidly in a short time, an instantaneous large fluctuation is given to a request TRQ or an incremental correction (incremental correction amount calculation) of a target TH opening described later. Therefore, in the present embodiment, as indicated by the dotted line 44, the hold process is performed assuming that the target LC pressure has not changed from time T2 to T3.

  Returning to FIG. 4, if the determination in step S <b> 2 is No, in step S <b> 5, the request TRQ or the target TH opening is incrementally corrected. This incremental correction will be described below with reference to FIGS.

  First, with reference to FIG. 6 and FIG. 7, the incremental correction for suppressing the acorn will be described. Note that this incremental correction for suppressing dongkuk is a correction that has been performed conventionally. FIG. 6 is a diagram illustrating a change over time such as a target TH opening degree to be controlled. FIG. 7 is a diagram showing the relationship between the target LC pressure and the correction gain. Here, the correction gain corresponds to the filtering gain used in the filtering process 33 of FIG.

  In FIG. 6A, the accelerator pedal opening 46 is turned on (opened) at time T1, and acceleration of the vehicle is started. The target LC pressure in FIG. 6B is increased stepwise as indicated by a line 47 after time T1. At this time, if no incremental correction of the required TRQ or the target TH opening is performed, the target TH opening in FIG. 6C, for example, rapidly rises at time T1 as indicated by a line 48. As a result, there is a risk that a dongkuk may be generated, preventing smooth acceleration of the vehicle.

  Therefore, in the present embodiment, as illustrated in FIG. 7, the correction gain 52 is reduced according to the target LC pressure. The horizontal axis in FIG. 7 is the target LC pressure (reference numeral 47 in FIG. 6B), and the LC loose and LC tight brackets indicate whether the clutch lock-up state is loose or tight, respectively. In other words, LC tight means that the lockup clutch 7 of FIG. 1 is completely (tightly) connected (engaged), and LC loose means that the engagement is loose. As illustrated in FIG. 7, when the correction gain 52 is decreased stepwise as the target LC pressure increases, the target throttle (TH) opening degree in FIG. It gradually increases from T1. This gradual rise in the target TH opening corresponds to a change obtained as a result of the stepwise increase in the TH opening shown in FIG. The gentle rise of the TH opening as exemplified by this line 49 makes it possible to suppress or alleviate the occurrence of cornflowers during acceleration.

  Next, with reference to FIGS. 8 and 9, a description will be given of a case where the required TRQ or the target TH opening is incrementally corrected according to the LC pressure during deceleration of the vehicle. FIG. 8 is a diagram showing a control flow of incremental correction according to the LC pressure. FIG. 9 is a diagram showing a time change (a) of the LC pressure and a time change (b) of the target TH opening.

  In step S10 of FIG. 8, it is determined whether or not the LC pressure during deceleration is zero. Here, the target LC pressure is used as the LC pressure, but an actual LC pressure detected by the hydraulic sensor 5b (FIG. 1) may be used. If this determination is Yes, the correction coefficient α1 is selected in step S11. The correction coefficient α1 is a correction coefficient when the LC pressure during deceleration with respect to the increment of the base TH opening (or request TRQ) is zero. When the determination in step S10 is No, the correction coefficient α2 is selected in step S12. The correction coefficient α2 is a correction coefficient when the LC pressure during deceleration with respect to the increment of the base TH opening (or request TRQ) is greater than zero (LC pressure> 0). Here, the base TH opening (or request TRQ) is a TH opening (or request TRQ) set in advance corresponding to the target LC pressure.

  In the next step S13, the increment of the TH opening (or request TRQ) is multiplied by the selected correction coefficient α1 or α2 to calculate the increment of the TH opening (or request TRQ). The difference in the incremental correction amount depending on the correction coefficient α1 or α2 will be described with reference to FIG.

  FIG. 9A illustrates a case where the target LC pressure during deceleration is zero (LC = 0) and a case where the target LC pressure is greater than zero (LC> 0). During acceleration, both LC = 0 and LC> 0 indicate a temporal change in the target LC pressure indicated by the line 53. That is, line 53 actually includes two cases where LC = 0 and LC> 0. Line 54 shows the change over time of the actual LC pressure when the target LC pressure during deceleration is zero, and line 55 shows the change over time of the actual LC pressure when the target LC pressure during deceleration is greater than zero. Show. As is apparent from the figure, when the target LC pressure during deceleration is greater than zero, the actual LC pressure reaches the target LC pressure earlier during acceleration than when the target LC pressure during deceleration is zero. Therefore, in order to alleviate a sudden torque increase, the correction coefficient α2 when the target LC pressure is greater than zero is set to be smaller than the correction coefficient α1 when the target LC pressure is zero (α2 <α1).

  As a result, as exemplified by the curve 56 in FIG. 9B, the TH opening (or required TRQ) during acceleration can be gradually increased. On the contrary, when the target LC pressure is zero, by adopting a correction coefficient α1 larger than the correction coefficient α2, the TH opening during acceleration (or as illustrated by the curve 57 in FIG. 9B) (or The request TRQ) can be raised relatively early. Thus, according to the present embodiment, the TH opening (or request TRQ) is increased by changing the correction coefficient for the increment of the base TH opening (or request TRQ) according to the LC pressure during deceleration. It is possible to suppress or alleviate the occurrence of cornflowers during acceleration due to a gradual rise. Instead of changing the correction coefficient α1 or α2, the correction gain of FIG. 7 may be changed according to the determination result of step S10 of FIG.

  Next, with reference to FIGS. 10 and 11, another embodiment in the case of performing incremental correction of the required TRQ or the target TH opening according to the LC pressure during deceleration of the vehicle will be described. In this embodiment, the correction coefficient (gain) is changed according to the magnitude of the LC pressure during deceleration. FIG. 10 is a diagram showing the time change (a) of the LC pressure and the time change (b) of the target TH opening. FIG. 11 is a diagram showing the relationship between the current LC pressure and the correction gain. Here, the correction gain corresponds to the filtering gain used in the filtering process 33 of FIG.

  FIG. 10A illustrates three levels of the target LC pressure during deceleration: small (for example, zero), medium, and large (full tight). The level of the LC pressure is not limited to three levels, and may be divided into two levels or four or more levels. When accelerating, the target LC pressure changes with time indicated by a line 58 in any of the three stages (small, medium, large) of the target LC pressure during deceleration. That is, line 58 actually includes these three stages. Lines 59, 60, and 61 indicate temporal changes in the actual LC pressure when the magnitude of the LC pressure during deceleration is large (full tight), medium, and small (for example, zero). The smaller the difference between the LC pressure during deceleration and the target LC pressure during acceleration following the deceleration, the faster the actual LC pressure reaches the target LC pressure during acceleration.

  Therefore, in this embodiment, in order to alleviate a sudden torque increase, as illustrated in FIG. 11, the correction gain is decreased stepwise according to the current LC pressure direction, and at the same time, the LC being decelerated further The correction gain during acceleration is varied (increased or decreased) according to the pressure level. The horizontal axis in FIG. 11 indicates the current LC pressure direction, and LC loose and LC tight mean that the clutch lock-up state is loose or tight, respectively. Lines 65, 66, and 67 indicate changes in the correction gain when the LC pressure during deceleration is small (for example, zero), medium, and large (full tight). As is clear from the figure, the correction gain is made smaller (larger) as the LC pressure during deceleration becomes larger (smaller).

  Specifically, when the LC pressure during deceleration is smaller than the target LC pressure during acceleration following the deceleration, the larger the difference between the LC pressure during deceleration and the target LC pressure during acceleration, the greater the difference based on the target LC pressure. The correction gain (FIG. 7) is increased. When the LC pressure during deceleration is greater than the target LC pressure during acceleration following the deceleration, the correction gain based on the target LC pressure increases as the difference between the LC pressure during deceleration and the target LC pressure during acceleration increases. (FIG. 7) is made smaller.

  As a result, as illustrated in FIG. 10B, the TH opening (or required TRQ) during acceleration can be gradually increased. In FIG. 10B, lines 62, 63, and 64 indicate the TH opening (or required TRQ) when the LC pressure during deceleration is small (for example, zero), medium, and large (full tight). Showing change. As is apparent from the figure, as the LC pressure during deceleration is larger (smaller), the TH opening (or required TRQ) rises more slowly (early). This makes it possible to suppress or mitigate the occurrence of dongwei during acceleration.

  Next, with reference to FIGS. 12 and 13, a case will be described in which incremental correction of the requested TRQ or the target TH opening is performed according to the LC control mode during deceleration of the vehicle. FIG. 12 is a diagram showing a control flow of incremental correction according to the LC control mode. FIG. 13 is a diagram showing a time change (a) in the LC control mode and a time change (b) in the target TH opening.

  In step S20 of FIG. 12, it is determined whether the LC control mode during deceleration is off. If this determination is Yes, the correction coefficient α3 is selected in step S21. The correction coefficient α3 is a correction coefficient when the LC control mode during deceleration with respect to the increment of the base TH opening (or request TRQ) is off. When the determination in step S20 is No, that is, when the LC control mode during deceleration is on, the correction coefficient α4 is selected in step S22. The correction coefficient α4 is a correction coefficient in the case where the LC control mode during deceleration with respect to the increment of the base TH opening (or request TRQ) is on. Here, the base TH opening (or request TRQ) is a TH opening (or request TRQ) set in advance corresponding to the target LC pressure, as in the case of FIG.

  In the next step S23, the increment of the TH opening (or request TRQ) is multiplied by the correction coefficient α3 or α4 to calculate the incremental correction amount of the TH opening (or request TRQ). The difference in the incremental correction amount depending on the correction coefficient α3 or α4 will be described with reference to FIG.

  FIG. 13A shows a state where the LC control mode is turned on during acceleration from the state where the LC control mode during deceleration is turned off or on. When the LC control mode during deceleration continues from the ON state to the acceleration state, the clutch lockup is maintained as it is, so that a sudden torque increase is likely to occur. Therefore, in order to alleviate the sudden torque increase, the correction coefficient α4 when the LC control mode during deceleration is on is set smaller than the correction coefficient α3 when the LC control mode is off (α4 <α3). .

  As a result, as illustrated as a broken line LCON in FIG. 13B, the TH opening (or required TRQ) during acceleration can be gradually increased. On the other hand, when the LC control mode is off, by adopting a correction coefficient α3 that is larger than the correction coefficient α4, as illustrated by the solid line LC OFF in FIG. Alternatively, the request TRQ) can be raised relatively early. As described above, according to the present embodiment, the TH opening (or request TRQ) is changed by changing the correction coefficient for incrementing the TH opening (or request TRQ) as a base in accordance with the LC control mode during deceleration. It is possible to suppress or alleviate the occurrence of cornflowers at the time of acceleration by the gentle rise of. Instead of changing the correction coefficient α3 or α4, the correction gain of FIG. 7 may be changed according to the determination result of step S20 of FIG.

  Next, with reference to FIGS. 14 and 15, another embodiment that performs incremental correction of the required TRQ or the target TH opening according to the LC control mode during deceleration of the vehicle will be described. In this embodiment, the LC control mode is further finely divided. FIG. 14 is a diagram showing a time change (a) in the LC control mode and a time change (b) in the target TH opening. FIG. 15 is a diagram illustrating the relationship between the current LC pressure and the correction gain. Here, the correction gain corresponds to the filtering gain used in the filtering process 33 of FIG.

  In FIG. 14 (a), the LC control mode during deceleration is switched from three modes of off (LC OFF), feedback (LC F / B), and on-tight (LC full-tight) to an on-time (LC ON) mode during acceleration. It shows the state to become. Here, the LC F / B mode is a mode in which the LC pressure is feedback controlled to a predetermined value (between OFF and ON (full tight)). When the LC control mode during deceleration is on (including LCF / B) and continues to be on even during acceleration, the clutch lock-up is maintained as it is, and a sudden torque increase is likely to occur.

  Therefore, in order to alleviate the sudden torque increase, in the present embodiment, as illustrated in FIG. 15, the correction gain is reduced stepwise according to the current LC pressure direction, and at the same time, the deceleration is further reduced. The correction gain during acceleration is varied (increased or decreased) according to the LC control mode. The horizontal axis in FIG. 15 indicates the current LC pressure direction, and LC loose and LC tight mean that the clutch lock-up state is loose or tight, respectively. Lines 72, 73, and 74 indicate changes in correction gain when the LC control mode during deceleration is LC OFF, LC F / B, and LC full tight. As is apparent from the figure, the correction gain is further decreased as the LC control mode during deceleration is shifted from LC OFF to LC full tight.

  As a result, as illustrated in FIG. 14B, the TH opening (or required TRQ) at the time of acceleration can be gradually increased. In FIG. 14B, lines 68, 69, and 70 indicate changes in the TH opening (or required TRQ) when the LC control mode during deceleration is LC OFF, LC F / B, and LC full tight. As is clear from the figure, the rise of the TH opening (or required TRQ) becomes slower in the order of LC OFF (68), LC F / B (69), and LC full tight (70). This makes it possible to suppress or mitigate the occurrence of dongwei during acceleration.

  Next, with reference to FIGS. 16 and 17, a case will be described in which incremental correction of the required TRQ or the target TH opening is performed in accordance with the difference between the LC pressure during deceleration of the vehicle and the LC pressure during acceleration. FIG. 16 is a diagram showing a control flow of incremental correction according to the difference between the LC pressure during deceleration and the LC pressure during acceleration. FIG. 17 is a diagram showing a temporal change (a) in the difference in LC pressure and a temporal change (b) in the target TH opening.

  In step S30 of FIG. 16, it is determined whether or not the vehicle is decelerating. Specifically, for example, it is determined whether or not the accelerator opening (AP) is a predetermined value or less. If this determination is Yes, the present control is terminated after monitoring the LC pressure during deceleration in step S35.

  When the determination in step S30 is No, in step S31, the LC pressure during deceleration is temporarily held in the memory. In step S32, a differential LC pressure between the held LC pressure during deceleration and the current LC pressure during acceleration is calculated. For example, ΔP1 and ΔP2 in FIG. 17A correspond to the differential LC pressure. FIG. 17A is basically the same as FIG. 9A already described, and the same reference numerals are assigned to the lines having the same meaning. That is, lines 53, 54, and 55 indicate the target LC pressure, the actual LC pressure when the target LC pressure during deceleration is zero, and the actual LC pressure when the target LC pressure during deceleration is greater than zero, respectively. The differential LC pressure ΔP1 is a difference between zero LC pressure during deceleration and LC pressure during acceleration. Similarly, the differential LC pressure ΔP2 is a difference between the LC pressure during acceleration and the LC pressure during acceleration when the LC pressure during deceleration is greater than zero. The target LC pressure is used as the LC pressure, but an actual LC pressure detected by the hydraulic sensor 5b (FIG. 1) may be used.

  In step S33, a correction coefficient is calculated according to the calculated differential LC pressure. This correction coefficient is a correction coefficient for the increment of the TH opening (or required TRQ) that is the base described above. In step S34, the increment of the TH opening (or request TRQ) is calculated by multiplying the increment of the base TH opening (or request TRQ) by the calculated correction coefficient. The difference in the incremental correction amount according to the correction coefficient will be described with reference to FIG.

  As is clear from FIG. 17A, the actual LC pressure reaches the target LC pressure at the time of acceleration earlier in the case of the small differential LC pressure ΔP1 than in the case of the large differential LC pressure ΔP2. Therefore, in order to mitigate a rapid torque increase, the correction coefficient αp1 at the differential LC pressure ΔP1 is set to be smaller than the correction coefficient αp2 at the differential LC pressure ΔP2 (αp1 <αp2).

  As a result, as illustrated as a curve 76 in FIG. 17B, the TH opening (or required TRQ) during acceleration can be gradually increased. Conversely, in the case of a large differential LC pressure ΔP2, by adopting a correction coefficient αp2 that is larger than the correction coefficient αp1, as exemplified by the curve 75 in FIG. 17B, the TH opening during acceleration (or The request TRQ) can be raised relatively early. As described above, according to this embodiment, the correction coefficient for incrementing the base TH opening (or request TRQ) is changed according to the difference between the LC pressure during deceleration of the vehicle and the LC pressure during acceleration. Thus, the TH opening (or the required TRQ) can be gently raised to suppress or alleviate the occurrence of donghae during acceleration.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and can be modified and used without departing from the spirit of the present invention. For example, instead of multiplying the correction coefficient exemplified in FIG. 8 by the base TH opening (or TRQ) value and performing correction, the correction may be performed by addition / subtraction with respect to the base TH opening (or TRQ) value. In short, any correction may be used as long as the target LC pressure and the deceleration LC pressure are tighter so that ΔTH or ΔTRQ can be reduced. Also, a base gain used for the filtering process of the block 33 (FIG. 2) is calculated from the engine speed NE, the accelerator pedal opening AP, and the gear stage, and the base gain is corrected based on the target LC pressure and the LC pressure during deceleration. You may make it calculate the gain used for the filtering process of the block 33 by multiplying or adding / subtracting the gain.

V Vehicle W Front wheel 1 Control device 2 ECU
3 Engine 6 Torque converter 7 Lock-up clutch 9 Automatic transmission 14 Throttle valve 22 Accelerator opening sensor 24 Throttle valve opening sensor

Claims (7)

Used in a vehicle with an automatic transmission having an internal combustion engine and a torque converter with a lock-up clutch, and when the vehicle is accelerated due to the accelerator operation, the target output of the internal combustion engine accompanying the accelerator operation is changed to the output change of the internal combustion engine. A control device for an internal combustion engine comprising a restriction means for restricting the amount to a predetermined speed,
The regulating means on the basis of the measured value or the target value of the operating pressure of the lock-up clutch immediately before the previous SL acceleration, the more the actual value or the target value is large, the restriction value setting means for setting a small predetermined speed A control device for an internal combustion engine. The restriction value setting means is configured such that a change from the actually measured value or the target value to the target operating pressure makes the lock-up clutch more tightly engaged based on the target operating pressure of the lock-up clutch during acceleration. The control device for an internal combustion engine according to claim 1, wherein the predetermined speed is set to be smaller as it goes in a direction. The said regulation value setting means sets the said predetermined speed smaller when the control about the operating pressure of the said lockup clutch is performed than the time when the said control is not performed. Control device for internal combustion engine. The control of the internal combustion engine according to any one of claims 1 to 3, wherein the restriction value setting means sets the predetermined speed to be smaller as a difference between the actual measurement value or the target value and the target operating pressure is smaller. apparatus. The internal combustion engine includes a throttle valve that controls an intake air amount, the restricting means restricts a target opening of the throttle valve, and the restriction value setting means sets an allowable change amount of the target opening. The control apparatus for an internal combustion engine according to any one of claims 1 to 4 . In the state where the automatic transmission temporarily decreases the target operating pressure after increasing the target operating pressure of the lock-up clutch to a predetermined value as the vehicle is accelerated, the regulation value setting means includes: The control device for an internal combustion engine according to any one of claims 1 to 4 , wherein the predetermined speed is set assuming that the target operating pressure is maintained at the predetermined value. In the state where the automatic transmission temporarily decreases the target operating pressure after increasing the target operating pressure of the lock-up clutch to a predetermined value as the vehicle is accelerated, the regulation value setting means includes: The control device for an internal combustion engine according to claim 5 , wherein an allowable change amount of the target opening is set assuming that the target operating pressure is held at the predetermined value.

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