JP4807448B2 - Output control device for internal combustion engine - Google Patents

Description

  The present invention relates to an output control device for an internal combustion engine.

  As an output control of the internal combustion engine, a target output torque of the engine is calculated based on an operation amount of an accelerator pedal by a driver, and the engine output torque is adjusted by adjusting an intake air amount based on the target output torque. So-called torque demand control is known.

  For example, in the control device described in Patent Document 1, a target drive shaft torque is obtained based on an accelerator operation amount and a vehicle speed, and the target drive shaft torque is divided by a final gear ratio to calculate a target output shaft torque of the transmission. Like to do. Then, this target output shaft torque is divided by the torque multiplication rate of the transmission and the torque converter to calculate the target output torque of the engine, and the throttle valve opening is set based on this target output torque and the engine speed. Like to do.

  As described in this document, if the target output torque of the engine is calculated in consideration of torque conversion in the transmission, the transmission gear ratio (the rotational speed of the input shaft / the rotational speed of the output shaft) It is possible to calculate the target output torque in correspondence with.

JP-A-8-218919

As described above, when calculating the target output torque of the engine in consideration of torque conversion in the transmission, the following inconvenience may occur.
That is, in a vehicle equipped with an automatic transmission, when the accelerator pedal is depressed during steady running and shifts to an acceleration state, the gear ratio of the automatic transmission changes from a small state (so-called high gear state) to a large state (so-called low gear state). Changed to

  Although the target output torque during acceleration is made larger than during steady running, the acceleration force tends to be insufficient particularly when the gear ratio is small at the beginning of acceleration. Therefore, even if the amount of depression of the accelerator pedal is small, the target output torque immediately after the depression is suddenly increased, and the target output torque that is rapidly increased is decreased as the gear ratio is increased.

  In this way, by changing the target output torque according to the gear ratio, sufficient acceleration force can be obtained even at the beginning of acceleration when the gear ratio is small, and smooth acceleration force can be obtained from the beginning of acceleration to the completion of acceleration. It becomes possible.

  Here, when the target output torque is suddenly increased at the initial stage of acceleration or the like, the opening of the throttle valve is also suddenly increased in accordance with the change of the target output torque, and the intake air amount rapidly increases. Thus, when the intake air amount rapidly increases, knocking is likely to occur due to a delay in changing the fuel injection amount with respect to the rapidly increased intake air amount or a delay in knocking control with respect to the rapidly increased intake air amount. In particular, when the gear ratio is small, the drive resistance from the output shaft of the internal combustion engine to the input shaft of the automatic transmission is large, so even if the actual output torque of the engine suddenly increases, the increase is quickly Can not communicate to. Therefore, immediately after the output torque of the engine suddenly increases, the engine load increases temporarily, but knocking is more likely to occur.

  Further, since the drive resistance is large when the gear ratio is small, there is a possibility that a shock may occur in the vehicle drive system, although temporarily, immediately after the output torque of the engine suddenly increases.

  The present invention has been made in view of such circumstances, and the object of the present invention is knocking or a drive system that may occur due to a sudden increase in target output torque when the gear ratio of the automatic transmission is small. Another object of the present invention is to provide an output control device for an internal combustion engine that can suitably suppress such shock.

In the following, means for achieving the above object and its effects are described.
The invention according to claim 1 is applied to an internal combustion engine that is mounted on a vehicle equipped with an automatic transmission and includes an air amount metering means for metering an intake air amount. And an output control device for an internal combustion engine that calculates a target output torque of the engine based on a state of a gear ratio of the automatic transmission and calculates a target drive amount of the air amount metering means based on the target output torque. When the current value of the gear ratio of the automatic transmission when the input shaft and the output shaft of the automatic transmission are rotating in the same direction is smaller than a predetermined value, the automatic transmission is calculated based on the target output torque. The gist is to limit the target drive amount to a value equal to or less than a preset upper limit value.

  In this configuration, the target output torque of the engine is calculated based on the accelerator pedal operation amount, the vehicle speed, and the speed ratio of the automatic transmission, and the intake air amount is adjusted based on the target output torque. The target drive amount of the quantity means is calculated.

  Here, according to the configuration, when the current value of the gear ratio of the automatic transmission that is made variable is smaller than a preset predetermined value, the target drive amount calculated based on the target output torque is set in advance. It is limited to a value that is less than or equal to the set upper limit. In this way, when the gear ratio is small, the drive amount of the air amount metering means that regulates the intake air amount is limited. Therefore, even if the target output torque increases rapidly while the gear ratio is small, the intake air amount The sudden increase can be suppressed, and the actual increase in output torque can also be suppressed. Therefore, the target output torque rapidly increases when the gear ratio is small, and thus, the knocking that is likely to occur due to the sudden increase in the intake air amount, or the drive that is likely to occur due to the sudden increase in the output torque due to the sudden increase in the target output torque. The shock in the system can be suitably suppressed.

  In the configuration according to claim 1, the predetermined value for determining whether the current value of the gear ratio of the automatic transmission is large or small may be the knocking or drive system when the target output torque increases rapidly. It is desirable to set a gear ratio that may cause a shock.

  With respect to the setting of the upper limit value, as described in claim 2, the drive amount of the air amount metering means is such that the output torque of the engine is reduced by a predetermined ratio with respect to the maximum output torque according to the engine speed. By setting this, the sudden increase in the output torque of the engine can be appropriately suppressed through the limitation of the drive amount.

  According to a third aspect of the present invention, in the output control device for an internal combustion engine according to the second aspect, the output torque of the engine which is smaller by the predetermined ratio is from a region where the change amount of the output torque is larger than the change amount of the drive amount. The gist is that the output torque is within the change region when changing to a small region.

  When the drive amount of the air amount adjustment means for adjusting the intake air amount is small and the intake air amount is small, the change rate of the intake air amount with respect to the change amount of the drive amount is large, and the change rate of the engine output torque is also It tends to grow. On the other hand, when the drive amount is large and the intake air amount is large, the change rate of the intake air amount with respect to the change amount of the drive amount tends to be small, and the change rate of the engine output torque tends to be small. Therefore, as in the same configuration, the output torque in the change region when the change rate of the output torque with respect to the change amount of the drive amount of the air amount metering unit changes from the large region to the small region is reduced by the predetermined ratio. By setting the output torque of the engine, a somewhat high output torque can be obtained even if the drive amount of the air amount metering means is limited by the upper limit value. Therefore, even when the upper limit value is set to suppress a sudden increase in the intake air amount, the driver's acceleration request can be suitably satisfied.

  The air quantity metering means is a throttle valve provided in the intake passage of the engine as in the invention described in claim 4, or the engine as in the invention described in claim 5. It is possible to adopt a configuration in which the intake valve is a valve characteristic variable mechanism that adjusts the intake air amount by changing at least one of the maximum lift amount and the valve opening period.

1 is a schematic diagram showing a schematic configuration of a vehicle to which the output control device according to the present invention is embodied and an internal combustion engine mounted on the vehicle. The conceptual diagram of the integrated control in the embodiment. The graph which shows a fuel consumption optimal line. The timing chart which shows the change aspect of intake air amount when performing output control corresponding to an acceleration request | requirement. The flowchart which shows the procedure about the correction process of the throttle opening in the embodiment. The graph which shows the relationship between throttle opening and output torque. The timing chart which shows the change aspect of the target throttle opening and intake air amount when the correction process is performed. The flowchart which shows the procedure about the correction process of the throttle opening in 2nd Embodiment. The timing chart which shows the setting aspect of the target throttle opening when the correction process is performed. The flowchart which shows the procedure about the correction process of the throttle opening in 3rd Embodiment. The timing chart which shows the setting aspect of the target throttle opening when the correction process is performed. The timing chart which shows the setting aspect of the target throttle opening when the correction process is performed. The schematic diagram which shows schematic structure of the internal combustion engine in the modification of each embodiment. The graph which shows the change aspect of the maximum lift amount and valve opening period of an intake valve through the drive of a valve characteristic variable mechanism.

(First embodiment)
Hereinafter, a first embodiment of an internal combustion engine output control apparatus according to the present invention will be described with reference to FIGS.

  As shown in FIG. 1, an internal combustion engine 10 is mounted on this vehicle. An intake passage 13 for sending air to the combustion chamber is connected to the internal combustion engine 10, and a throttle valve 14 as an air amount adjustment means for adjusting the intake air amount is provided in the intake passage 13. Is provided. The opening degree of the throttle valve 14 is controlled by an electric motor. Then, fuel corresponding to the amount of the metered intake air is injected from the fuel injection valve, and an air-fuel mixture, which is a mixture of air and fuel, is burned in the combustion chamber. Output is obtained.

The crankshaft 12 of the internal combustion engine 10 is connected to the torque converter 20, and the output shaft of the torque converter 20 is connected to the input shaft of the planetary gear mechanism 22. The planetary gear mechanism 22 switches between forward and backward movement of the vehicle. An output shaft of the planetary gear mechanism 22 is connected to an input shaft 32 of a continuously variable transmission (hereinafter referred to as CVT) 30 that is an automatic transmission, and an output shaft 34 of the CVT 30 is It is connected to the drive wheels of the vehicle. The CVT 30 is provided with a first pulley 30a that rotates integrally with the input shaft 32, a second pulley 30b that rotates together with the output shaft 34, a belt 30c that transmits the rotational force of the first pulley 30a to the second pulley 30b, and the like. ing. Then, by continuously varying the pulley width of the first pulley 30a and the second pulley 30b, a quotient (Nin / Nout) obtained by dividing the rotational speed Nin of the input shaft 32 by the rotational speed Nout of the output shaft 34, that is, a speed change The ratio R is continuously varied. In the speed change by the CVT 30, the speed ratio R can be widely changed and the speed ratio R can be continuously varied as compared with the stepped transmission, so that the operation of the internal combustion engine 10 is brought to the fuel efficiency optimum line. It can be done in the near part.

  The torque converter 20 is provided with an oil pump that generates the control hydraulic pressure of the CVT 30. The first pulley 30 a and the second pulley 30 b have their pulley widths controlled through hydraulic control by the hydraulic control circuit 50.

  Further, the vehicle and the internal combustion engine 10 are provided with various sensors for detecting the running state and the engine operating state. For example, the accelerator pedal 60 operated by the driver is provided with an accelerator sensor 70 that detects an accelerator operation amount ACCP that is an operation amount thereof. Further, a vehicle speed sensor 71 for detecting the vehicle speed SPD is provided on the vehicle wheel, and a crank angle sensor 72 for detecting the engine rotational speed NE is provided in the vicinity of the crankshaft 12 of the internal combustion engine 10. The throttle valve 14 is provided with a throttle sensor 73 for detecting the throttle opening degree TA which is the opening degree thereof, and the input shaft 32 of the CVT 30 detects the input rotational speed Nin which is the rotational speed of the input shaft 32. A rotational speed sensor 74 is provided.

  Various controls of the internal combustion engine 10 and the CVT 30 are performed by the electronic control unit 40. The electronic control unit 40 includes a CPU that executes arithmetic processing related to various controls, a ROM that stores programs and data necessary for the control, a RAM that temporarily stores the arithmetic results of the CPU, and signals between the outside The input / output port for inputting / outputting is provided.

  The electronic control unit 40 then performs output control such as intake air amount control and fuel injection control of the internal combustion engine 10 or shift control of the CVT 30 based on the engine operating state and vehicle running state detected by the various sensors described above. I do.

  More specifically, the target output torque Tp of the internal combustion engine 10 is calculated based on the operation amount of the accelerator pedal 60 by the driver, and the intake air amount and the like are adjusted based on the target output torque Tp. So-called torque demand control is performed to control the output torque of the engine. Further, such output control and shift control of the CVT 30 are integratedly controlled, and the internal combustion engine 10 is operated at a portion close to the fuel efficiency optimum line.

FIG. 2 shows an outline of the integrated control. In this integrated control, first, the target engine output Pp requested by the driver is calculated based on the accelerator operation amount ACCP and the vehicle speed SPD.
Then, shift control and output control are performed based on the target engine output Pp.

  In the shift control, the target input rotational speed Ninp of the first pulley 30a is set so that the set target engine output Pp can be realized on the fuel efficiency optimum line of the internal combustion engine 10. As shown in FIG. 3, the fuel efficiency optimal line is a line indicating a correspondence relationship between the engine output P and the engine rotational speed NE that can minimize the fuel consumption. The input shaft 32 that rotates integrally with the first pulley 30 a is connected to the crankshaft 12 via the torque converter 20 and the planetary gear mechanism 22. Accordingly, the target input rotational speed Ninp when the target engine output Pp is obtained with the fuel consumption being minimized is also calculated based on the fuel efficiency optimum line.

  Next, a control amount of the CVT 30 is calculated based on the target input rotation speed Ninp, and the CVT 30 is shifted based on the control amount. Here, the pulley widths of the first pulley 30a and the second pulley 30b are adjusted so that the input rotation speed Nin of the input shaft 32 detected by the rotation speed sensor 74 and the target input rotation speed Ninp coincide with each other.

  On the other hand, in the output control, the target output torque Tp is calculated based on the calculated target engine output Pp and the actual rotational speed of the first pulley 30a, that is, the input rotational speed Nin. This target output torque Tp is calculated based on the following equation (1).

Tp = (Pp × K) / Nin (1)
Tp: Target output torque [N · m]
Pp: Target engine output Pp [kW]
Nin: Input rotation speed [rpm]
K: constant = 9549.3

Then, a target throttle opening degree TAp is calculated based on the target output torque Tp, and the opening degree of the throttle valve 14 is adjusted so that the target throttle opening degree TAp and the throttle opening degree TA detected by the throttle sensor 73 coincide with each other. Adjusted. By adjusting the opening of the throttle valve 14 in this way, an intake air amount corresponding to the target output torque Tp is introduced into the combustion chamber, and fuel corresponding to the intake air amount is injected from the fuel injection valve. The output torque T of the internal combustion engine 10 is adjusted to the target output torque Tp.

Further, during the acceleration of the vehicle, the following output control corresponding to the acceleration request by the driver is performed.
That is, when the accelerator pedal 60 is depressed during steady running of the vehicle and the vehicle shifts to an acceleration state, the gear ratio R of the CVT 30 is changed from a small state (so-called high gear state) to a large state (so-called high gear state). Low gear state).

  The target output torque Tp during acceleration is made larger than that during steady running due to an increase in the accelerator operation amount ACCP. However, particularly when the speed ratio R is small at the initial stage of acceleration, the acceleration force is insufficient. It is in an easy state. Therefore, even if the depression amount of the accelerator pedal 60 is small, the target output torque Tp immediately after the depression is suddenly increased, and the target output torque Tp that is rapidly increased as the speed ratio R is increased is decreased.

  Thus, by changing the target output torque Tp in accordance with the state of the gear ratio R, a sufficient acceleration force can be obtained even at the initial stage of acceleration when the gear ratio R is small, and smooth from the beginning of acceleration to the completion of acceleration. Acceleration can be obtained.

By the way, when the output control corresponding to the acceleration request is performed, the following inconvenience may occur.
For example, as shown in FIG. 4, when the accelerator pedal 60 is depressed at a time t1 while the speed ratio R is small, the target output torque Tp is equal to the case where the accelerator operation amount ACCP is relatively small. Increased rapidly. As the target output torque Tp rapidly increases, the opening of the throttle valve 14 (throttle opening TA) is also increased rapidly, and the intake air amount increases rapidly. Thus, when the intake air amount rapidly increases, knocking is likely to occur due to a delay in changing the fuel injection amount with respect to the rapidly increased intake air amount or a delay in knocking control with respect to the rapidly increased intake air amount. In particular, when the transmission gear ratio R is small, the driving resistance from the crankshaft 12 of the internal combustion engine to the input shaft 32 of the CVT 30 is large. Can not communicate to the side. Therefore, immediately after the output torque T of the engine suddenly increases, the engine load increases temporarily, but knocking is more likely to occur.

  In addition, since the drive resistance is large when the speed ratio R is small, there is a possibility that a shock may occur in the vehicle drive system, although it is temporary, immediately after the output torque T increases rapidly.

  Therefore, in this embodiment, by suppressing the sudden increase in the intake air amount and the output torque T through the throttle opening correction process described below, the target when the gear ratio R of the CVT 30 is small is suppressed. Knocking that may occur due to a sudden increase in the output torque Tp and occurrence of a shock in the drive system are suppressed.

FIG. 5 shows a processing procedure for the correction processing. This process is repeatedly executed by the electronic control device 40 every predetermined time.
When this process is started, it is first determined whether or not the current gear ratio R is equal to or less than a determination value A (S100). The determination value A is set to a gear ratio R that may cause the knocking or the drive system shock when the target output torque Tp increases rapidly.

  Then, when the current gear ratio R exceeds the determination value A (S100: NO), the present gear ratio R is large and there is no possibility that the above inconvenience occurs, and this processing is temporarily terminated. In this case, the opening degree of the throttle valve 14 is adjusted toward the target throttle opening degree TAp calculated based on the target output torque Tp.

  On the other hand, when the current gear ratio R is equal to or less than the determination value A (S100: YES), the following processing is continuously performed on the assumption that the current gear ratio R is small and the above problem may occur.

  First, the current engine speed NE is read (S110), and a guard value G for limiting the maximum value of the target throttle opening degree TAp is set based on the engine speed NE (S120). The guard value G is a throttle opening TA at which the engine output torque T is reduced by a predetermined ratio with respect to the maximum output torque Tmax corresponding to the engine rotational speed NE. More specifically, the guard value G is set based on the following principle. Is the value to be

  FIG. 6 shows the relationship between the throttle opening degree TA and the output torque T of the engine. As shown in FIG. 6, the change in the engine output torque T with respect to the change in the throttle opening degree TA differs for each engine speed. When the throttle opening TA is small and the intake air amount is small, the change rate of the intake air amount with respect to the change amount of the throttle opening TA is large and the change rate of the output torque T tends to be large (for example, NE = In the case of 1000 rpm, the region L shown in FIG. 6). On the other hand, when the throttle opening degree TA is large and the intake air amount is large, the change rate of the intake air amount with respect to the change amount of the throttle opening TA is small, and the change rate of the engine output torque T tends to be small (for example, When NE = 1000 rpm, the region S shown in FIG. 6). Therefore, in the present embodiment, a change region (eg, NE = At 1000 rpm, the output torque T in the region M) shown in FIG. 6 is set as the output torque T of the engine which is smaller by the predetermined ratio. Then, the throttle opening degree TA corresponding to the output torque T in the change region is set as the guard value G. Note that since the change region differs for each engine speed, the guard value G is variably set based on the engine speed NE. By setting the guard value G in this way, even if the target throttle opening degree TAp is limited by the guard value G, that is, the throttle opening degree TA is limited, a somewhat high output torque T can be obtained. Even if the guard value G is set to suppress the sudden increase in the intake air amount, the driver's acceleration request can be satisfied.

  Incidentally, in the internal combustion engine 10 according to the present embodiment, about 90% of the output torque T is within the change region with respect to the maximum output torque Tmax that differs for each engine speed. Therefore, the throttle opening degree TA corresponding to the output torque T that is 90% of the maximum output torque Tmax is obtained for each engine speed, and the throttle opening degree TA obtained for each engine speed is set as the guard value G. I am doing so. For example, as shown in FIG. 6, when the engine rotation speed NE is 1000 rpm, “G = G (1000)” is set as the guard value G corresponding to the rotation speed. When the engine rotational speed NE is 2000 rpm, “G = G (2000)”, which is larger than the guard value G (1000), is set as the guard value G corresponding to the rotational speed, and the engine rotational speed NE is 4000 rpm. In this case, “G = G (4000)” larger than the guard value G (2000) is set as the guard value G corresponding to the rotation speed. When the engine rotational speed NE is 6000 rpm, “G = G (6000)”, which is larger than the guard value G (4000), is set as the guard value G corresponding to the rotational speed.

  When the guard value G is set in step S120, it is next determined whether or not the currently set target throttle opening degree TAp is equal to or greater than the guard value G (S130). When the target throttle opening degree TAp is less than the guard value G (S130: NO), the present target throttle opening degree TAp is comparatively small and the above inconvenience may not occur. Is done. In this case, the opening degree of the throttle valve 14 is adjusted toward the target throttle opening degree TAp calculated based on the target output torque Tp.

  On the other hand, when the target throttle opening degree TAp is equal to or greater than the guard value G (S130: YEA), the target throttle opening degree TAp is corrected to the guard value G, and this process is temporarily terminated.

FIG. 7 shows an example of how the target throttle opening degree TAp is corrected by executing the correction process.
As described above, when the accelerator pedal 60 is depressed with the gear ratio R being small (time t1), even if the accelerator operation amount ACCP is relatively small, the target output torque Tp increases rapidly. Is done.

  At this time, when the current value of the gear ratio R is equal to or smaller than the determination value A, the target throttle opening degree TAp calculated based on the target output torque Tp is limited to be a value equal to or smaller than the guard value G. In this example, since the calculated target throttle opening degree TAp (illustrated by a two-dot chain line) exceeds the guard value G, the actual target throttle opening degree TAp is set to the guard value G. As a result, the intake air amount immediately after the target output torque Tp rapidly increases is gradually increased as compared with the case where the upper limit of the target throttle opening degree TAp is not limited (illustrated by a two-dot chain line).

  In this way, when the speed ratio R is small, the upper limit value of the opening of the throttle valve 14 that regulates the intake air amount is limited. Therefore, even if the target output torque Tp increases rapidly when the speed ratio R is small. As a result, the sudden increase in the intake air amount can be suppressed, and the actual increase in the output torque T can also be suppressed. Accordingly, the target output torque Tp rapidly increases when the speed ratio R is small, and thus, knocking that is likely to occur due to a sudden increase in the intake air amount, or a sudden increase in the output torque T due to a rapid increase in the target output torque Tp. Shock in the drive system that is likely to occur is suppressed.

In the present embodiment, by limiting the target throttle opening degree TAp with the guard value G, the following effects can also be obtained.
In general, in an internal combustion engine, when knocking occurs, knocking control is performed in which the ignition timing is retarded to suppress the occurrence of the knocking, and such knocking control is also performed in the internal combustion engine 10 of the present embodiment. . By the way, if the ignition timing is retarded, there is a demerit that the exhaust temperature increases or the output torque T decreases. Therefore, when the ignition timing is retarded, the exhaust temperature increases, the output torque T decreases, or the like. There is a permissible limit ignition timing. Here, when the throttle opening degree TA is in the vicinity of full open, the intake air amount is increased and the actual compression ratio is increased, so that knocking is likely to occur. Therefore, when the throttle opening degree TA is close to full open, the ignition timing retarded to suppress the occurrence of knocking may be close to the limit timing. Further, in some cases, the retarded ignition timing reaches the limit timing, and it may not be possible to suppress the occurrence of knocking only by retarding the ignition timing. In this regard, in the present embodiment, the target throttle opening degree TAp is limited by the guard value G, and the maximum opening degree of the throttle opening degree TA is also limited to the guard value G. Accordingly, when the throttle opening degree TA is limited, the throttle opening degree TA does not become fully open, and an increase in actual compression can be suppressed to some extent. Therefore, compared with the case where the throttle opening degree TA is close to full open, the ignition timing is an advance timing away from the above limit timing, and it is possible to sufficiently secure the ignition timing retard amount for suppressing knocking. it can. Therefore, the occurrence of knocking can be sufficiently suppressed even with the conventional knocking control.

  Further, as shown in FIG. 6, when the throttle opening degree TA is large and the intake air amount is large, the rate of change of the intake air amount with respect to the change amount of the throttle opening degree TA is small, and the output torque T of the engine The rate of change also tends to be small. Therefore, for example, when the driver increases or decreases the amount of operation of the accelerator pedal 60 and the change in the target output torque Tp at that time occurs within a region where the change rate of the output torque T is small, even if the target output is Even if the change amount of the torque Tp is small, the change amount of the target throttle opening degree TAp becomes large. Therefore, the opening degree of the throttle valve 14 also varies while changing greatly. As a result, the durability of the drive mechanism such as an electric motor for adjusting the opening degree of the throttle valve 14 may be lowered. . In this regard, in the present embodiment, the target throttle opening degree TAp is limited by the guard value G. Therefore, when the maximum opening degree of the throttle opening degree TA is limited to be equal to or less than the guard value G, The throttle opening TA does not enter the region where the change rate of the output torque T is small. Therefore, the durability of the drive mechanism such as the electric motor can be improved.

As described above, according to the present embodiment, the following operational effects can be obtained.
(1) The target throttle opening degree TAp calculated based on the target output torque Tp is set in advance when the current value of the gear ratio R of the CVT 30 that is variable is equal to or less than the determination value A (in high gear). The upper limit value is set to be equal to or less than the guard value G. Accordingly, the target output torque Tp rapidly increases when the speed ratio R is small, and this is caused by knocking that is likely to occur due to a sudden increase in the intake air amount, or by a sudden increase in the output torque due to a sudden increase in the target output torque Tp. It becomes possible to suitably suppress a shock in the drive system that becomes easy.

  (2) As the guard value G, the throttle opening TA is set so that the output torque T of the engine is reduced by a predetermined ratio with respect to the maximum output torque Tmax corresponding to the engine rotational speed NE. The sudden increase in the output torque T can be appropriately suppressed through the restriction of the throttle opening TA.

(3) As the output torque T of the engine that is smaller by the predetermined ratio, the output torque in the change region when the change amount of the output torque T with respect to the change amount of the throttle opening TA changes from a large region to a small region is set. I have to. Therefore, even when the guard value G is set so as to suppress the sudden increase in the intake air amount, the driver's acceleration request can be suitably satisfied.
(Second Embodiment)
Next, a second embodiment that embodies the output control apparatus for an internal combustion engine according to the present invention will be described with reference to FIGS.

  In the first embodiment, when the current value of the gear ratio R of the CVT 30 is equal to or smaller than the determination value A, the target throttle opening degree TAp calculated based on the target output torque Tp is limited to be equal to or smaller than the guard value G. I made it. However, if the target throttle opening degree TAp is limited in this way, the increase in the output torque T can be suppressed even when the acceleration demand of the vehicle driver is high, so that the driver's request can be satisfied appropriately. It becomes impossible.

  Therefore, in the present embodiment, the following process is performed as the throttle opening correction process, and a part of the correction process of the present embodiment is different from that of the first embodiment. Therefore, hereinafter, the output control apparatus according to the present embodiment will be described focusing on the differences.

FIG. 8 shows the procedure of the throttle opening correction process in this embodiment. This process is also repeatedly executed by the electronic control device 40 every predetermined time.
When this process is started, it is first determined whether or not the current gear ratio R is equal to or less than a determination value A (S200). The determination value A is set to a gear ratio R that may cause the knocking or the drive system shock when the target output torque Tp increases rapidly.

  When the current gear ratio R exceeds the determination value A (S200: NO), the current gear ratio R is large, and knocking or driving due to the occurrence of the above-described inconvenience, that is, a sudden increase in the target output torque Tp. This process is temporarily terminated, assuming that there is no possibility that a shock will occur in the system. In this case, the opening degree of the throttle valve 14 is adjusted toward the target throttle opening degree TAp calculated based on the target output torque Tp.

  On the other hand, if the current gear ratio R is equal to or less than the determination value A (S200: YES), whether or not the accelerator change amount ACCPH, which is the change amount of the accelerator operation amount ACCP within a predetermined time, is smaller than the determination value α. Is determined (S210). This determination value α is a prescribed value for determining whether the amount of increase in the amount of operation of the accelerator pedal 60 is large or small. As the value, whether the driver's acceleration request is high or low is appropriate. A value that can be determined is set.

  When the accelerator change amount ACCPH is equal to or larger than the determination value α (S210: NO), the driver's acceleration request is high, and therefore the target throttle opening degree TAp is the full opening degree TAmax that is the maximum driving amount of the throttle valve 14. (S260), the process is temporarily terminated. In this case, the opening degree of the throttle valve 14 is adjusted toward the fully opened opening degree TAmax, whereby the output torque T of the internal combustion engine 10 becomes the maximum output torque Tmax, thereby obtaining the maximum acceleration force.

  On the other hand, when the accelerator change amount ACCPH is less than the determination value α (S210: YES), since the driver's request for acceleration is low, in order to suppress the occurrence of the above inconvenience rather than securing the acceleration force, FIG. The processes of steps S110 to S140 shown are performed, and thereby the same effects as those of the first embodiment can be obtained.

FIG. 9 shows an example of a mode in which the target throttle opening degree TAp is corrected to the full opening degree TAmax by executing the correction process.
As described above, when the accelerator pedal 60 is depressed with the speed ratio R being small (time t1), the target output torque Tp is suddenly increased.

  At this time, when the current value of the speed ratio R is equal to or smaller than the determination value A and the accelerator change amount ACCPH is equal to or larger than the determination value α, the target throttle opening degree TAp calculated based on the target output torque Tp is It is corrected to the full opening degree TAmax. As a result, immediately after the accelerator pedal 60 is depressed, the throttle valve 14 is fully opened, the intake air amount is increased to the maximum, the engine output torque T becomes the maximum output torque Tmax, and the acceleration force is maximized. It will be obtained. As described above, when the acceleration demand by the driver is high, the output torque T is increased to the maximum, so that the high acceleration demand by the driver can be appropriately satisfied.

As described above, according to the present embodiment, in addition to the operational effects obtained in the first embodiment, the following operational effects can also be obtained.
(4) When the current value of the changeable gear ratio R of the CVT 30 that is variable is equal to or less than the determination value A (during high gear) and the accelerator change amount ACCPH is less than the determination value α, the target output torque Tp is set. The target throttle opening degree TAp calculated based on the limit value is limited to be equal to or less than a guard value G that is a preset upper limit value. Accordingly, the target output torque Tp rapidly increases in a state where the speed ratio R is small while satisfying the low acceleration requirement by the driver, and thus the knocking or the target output torque Tp, which is likely to occur due to the sudden increase in the intake air amount. It is possible to suitably suppress a shock in the drive system that is likely to occur due to a sudden increase in output torque due to a sudden increase.

(5) When the current value of the variable speed ratio R of the CVT 30 that is variable is less than or equal to the determination value A (high gear) and the accelerator change amount ACCPH is greater than or equal to the determination value α, the target output torque Tp is set. The target throttle opening degree TAp calculated based on this is changed to the full opening degree TAmax. Accordingly, it is possible to appropriately satisfy the high acceleration demand by the driver.
(Third embodiment)
Next, a third embodiment that embodies an output control device for an internal combustion engine according to the present invention will be described with reference to FIGS.

In the second embodiment, when the acceleration request from the driver is high, the throttle valve 14 is fully opened regardless of the degree of the request.
On the other hand, in this embodiment, by adding another process to the correction process described in the second embodiment, when the acceleration request from the driver is high, the degree of the request is met. The opening degree of the throttle valve 14 can be adjusted, and a part of the correction processing of this embodiment is different from that of the second embodiment. Therefore, hereinafter, the output control apparatus according to the present embodiment will be described focusing on the differences.

FIG. 10 shows the procedure of the throttle opening correction process in this embodiment. This process is also repeatedly executed by the electronic control device 40 every predetermined time.
When this process is started, it is first determined whether or not the current gear ratio R is equal to or less than a determination value A (S200). The determination value A is set to a gear ratio R that may cause the knocking or the drive system shock when the target output torque Tp increases rapidly.

  When the current gear ratio R exceeds the determination value A (S200: NO), this process is temporarily terminated. In this case, the opening degree of the throttle valve 14 is adjusted toward the target throttle opening degree TAp calculated based on the target output torque Tp.

  On the other hand, if the current gear ratio R is equal to or less than the determination value A (S200: YES), whether or not the accelerator change amount ACCPH, which is the change amount of the accelerator operation amount ACCP within a predetermined time, is smaller than the determination value α. Is determined (S210). This determination value α is a prescribed value for determining whether the amount of increase in the amount of operation of the accelerator pedal 60 is large or small. As the value, whether the driver's acceleration request is high or low is appropriate. A value that can be determined is set.

  When the accelerator change amount ACCPH is less than the determination value α (S210: YES), since the driver's request for acceleration is low, the above inconvenience occurs, that is, the target output torque Tp increases more rapidly than the acceleration force is secured. In order to suppress the occurrence of knocking and shock in the drive system, the processes of steps S110 to S140 shown in FIG. 5 are performed. And the effect similar to the said 1st Embodiment is obtained by this.

  On the other hand, if the accelerator change amount ACCPH is greater than or equal to the determination value α (S210: NO), the driver's acceleration request is high, so that the following processing is continued to satisfy such a request.

  First, a torque difference ΔT indicating the degree of deviation between the maximum output torque Tmax and the target output torque Tp at the current engine speed NE is calculated (S300). This torque difference ΔT is calculated based on the following equation (2).

ΔT = Tmax−Tp (2)
ΔT: Torque difference Tmax: Maximum output torque at the current engine speed NE
Tp: Current target output torque Tp

Then, it is determined whether or not the torque difference ΔT is less than the determination value C (S310). Here, the smaller the torque difference ΔT, the smaller the degree of divergence between the maximum output torque Tmax and the target output torque Tp, and the target output torque Tp is set closer to the maximum output torque Tmax. The degree of acceleration request of the driver can be estimated based on the value of the difference ΔT. Accordingly, the determination value C is appropriately set to a value that can be used to determine whether or not the degree of the request is very high when the driver's acceleration request is high.

  When the torque difference ΔT is less than the determination value C (S310: YES), the accelerator change amount ACCPH indicating the increase amount of the accelerator operation amount ACCP is very large, and the degree of acceleration request by the driver is high. It can be estimated that it is very high. Therefore, in this case, the target throttle opening degree TAp is corrected to the fully opened opening degree TAmax, which is the maximum drive amount of the throttle valve 14 (S320), and this process is temporarily terminated. When the process of step S320 is performed, the opening degree of the throttle valve 14 is adjusted toward the fully opened opening degree TAmax, so that the output torque T of the internal combustion engine 10 becomes the maximum output torque Tmax, so that the maximum Limited acceleration force is obtained.

  On the other hand, when the torque difference ΔT is equal to or greater than the determination value C (S310: NO), it can be estimated that the acceleration request by the driver is high, but the degree is relatively low. Therefore, in this case, the present process is temporarily terminated without correcting the target throttle opening degree TAp.

  FIG. 11 shows how the target throttle opening degree TAp is set when the accelerator modification amount ACCPH is equal to or larger than the determination value α and the torque difference ΔT is equal to or larger than the determination value C when the correction process is executed. An example is shown.

As described above, when the accelerator pedal 60 is depressed with the speed ratio R being small (time t1), the target output torque Tp is suddenly increased.
FIG. 11 shows an aspect of setting the target throttle opening degree TAp through the execution of the correction process when the driver's acceleration request is very high.

As described above, when the accelerator pedal 60 is depressed with the speed ratio R being small (time t1), the target output torque Tp is suddenly increased.
At this time, if the current value of the gear ratio R is equal to or less than the determination value A, the accelerator change amount ACCPH is equal to or greater than the determination value α, and the torque difference ΔT is less than the determination value C, the target output torque Tp is set. The target throttle opening degree TAp calculated based on this is corrected to the full opening degree TAmax. As a result, immediately after the accelerator pedal 60 is depressed, the throttle valve 14 is fully opened, the intake air amount is increased to the maximum, the engine output torque T becomes the maximum output torque Tmax, and the acceleration force is maximized. It will be obtained. Thus, when the acceleration request by the driver is very high, the output torque T is increased to the maximum, so that the very high acceleration request by the driver can be appropriately satisfied.

FIG. 12 shows an aspect of setting the target throttle opening degree TAp through execution of the correction process when the driver demands acceleration is relatively low but the degree is relatively low.
At time t1, when the accelerator pedal 60 is depressed while the gear ratio R is small, the target output torque Tp is suddenly increased.

  At this time, if the current value of the gear ratio R is not more than the determination value A, the accelerator change amount ACCPH is not less than the determination value α, and the torque difference ΔT is not less than the determination value C, the target throttle opening degree TAp Is not limited by the guard value G, but is set to a value calculated based on the target output torque Tp. Therefore, the opening degree of the throttle valve 14 is adjusted to an opening degree at which the target output torque Tp is obtained. Thus, when the current value of the gear ratio R is equal to or less than the determination value A and the accelerator change amount ACCPH is equal to or greater than the determination value α, the restriction of the target throttle opening degree TAp by the guard value G is released, and the driver Thus, an output torque T corresponding to a relatively high acceleration request can be obtained. Therefore, the acceleration request by the driver can be appropriately satisfied.

As described above, according to the present embodiment, in addition to the functions and effects obtained in the first and second embodiments, the following functions and effects can be obtained.
(6) When the current value of the gear ratio R of the CVT 30 is equal to or less than the determination value A predetermined value and the accelerator change amount ACPH is equal to or greater than the determination value α, the value calculated based on the target output torque Tp is set to the target throttle opening. It is set as the degree TAp. Therefore, an output torque T corresponding to a relatively high acceleration request by the driver can be obtained. Therefore, it becomes possible to appropriately satisfy the acceleration demands by such drivers.

  Further, the current value of the gear ratio R of the CVT 30 is equal to or less than the determination value A predetermined value, the accelerator change amount ACCPH is equal to or greater than the determination value α, and the maximum output torque Tmax and the target output torque Tp according to the engine speed NE When the torque difference ΔT indicating the degree of deviation from is smaller than the determination value C, the target throttle opening degree TAp is set to the full opening degree TAmax. Accordingly, it is possible to appropriately satisfy a very high acceleration request by the driver, and according to the embodiment, the high acceleration request by the driver is more appropriately matched to the degree compared to the second embodiment. It becomes possible to satisfy.

In addition, each said embodiment can also be changed as follows, for example.
Although the guard value G is variably set based on the engine speed, it may be a fixed value that is set as appropriate. For example, the smallest guard value G may be set at each engine rotation speed.

  Although the throttle opening degree TA corresponding to the output torque T that is 90% of the maximum output torque Tmax is set as the guard value G, the setting mode of the guard value G is not limited to this. In short, if the throttle opening degree TA corresponding to the output torque in the change region when the change amount of the output torque T changes from a large region to a small region is set as the guard value G, Similar effects can be obtained.

  In addition, as the guard value G, the throttle opening degree TA corresponding to the output torque in the change region is set, but the engine output is a predetermined ratio with respect to the maximum output torque Tmax corresponding to the engine rotation speed. The throttle opening TA at which the torque T becomes small may be set as the guard value G. Even in this case, the rapid increase of the engine output torque T can be appropriately suppressed through the restriction of the throttle opening TA.

  In the second embodiment, the torque difference ΔT is calculated in order to determine whether the deviation degree between the maximum output torque Tmax and the target output torque Tp is less than a predetermined value. In the aspect, it may be determined whether the divergence degree is less than a predetermined value. For example, a ratio of the target output torque Tp with respect to the maximum output torque Tmax is obtained, and when the ratio is larger than a preset value, it may be determined that the degree of divergence is less than a predetermined value.

  The automatic transmission in each of the above embodiments is a continuously variable transmission, and when changing the gear ratio R from a small state to a large state during vehicle acceleration, the gear ratio R can be continuously changed. It was a transmission. On the other hand, in the case of a stepped automatic transmission, when the vehicle is accelerating, the gear ratio is changed from a small state to a large state step by step, but when the gear ratio is small When the target output torque Tp increases rapidly, knocking as described above and a shock in the drive system are the same as in the case of the continuously variable transmission. Therefore, the present invention can be similarly applied to an output control device for an internal combustion engine mounted on a vehicle equipped with a stepped automatic transmission. In this case as well, effects similar to those of the above embodiments are obtained. be able to.

  In each of the above embodiments, the air amount metering means for metering the intake air amount is the throttle valve 14, but the present invention is similarly applied to an internal combustion engine having other air amount metering means. In this case, the same effects as in the above embodiments can be obtained.

  For example, the present invention can also be applied to an output control device for an internal combustion engine 100 including an air amount metering unit as shown in FIG. The air amount metering means shown in FIG. 13 includes a valve characteristic variable mechanism 103 as an air amount metering means for metering the intake air amount between the intake camshaft 101 and the intake valve 102. As shown in FIG. 14, the variable valve characteristic mechanism 103 is a mechanism that varies the maximum lift amount and the valve opening period of the intake valve, and the intake air amount is increased by increasing the maximum lift amount and the valve opening period. Is increased. When such a valve characteristic variable mechanism 103 is provided as an air amount metering means, target values of valve characteristics such as a maximum lift amount and a valve opening period that are variable by the valve characteristic variable mechanism 103 are the target throttle. The value corresponds to the opening degree TAp. Note that the present invention can be similarly applied to a case where a valve characteristic variable mechanism that adjusts the intake air amount by changing at least one of the maximum lift amount and the valve opening period of the intake valve is provided.

DESCRIPTION OF SYMBOLS 10 ... Internal combustion engine, 12 ... Crankshaft, 13 ... Intake passage, 14 ... Throttle valve, 20 ... Torque converter, 22 ... Planetary gear mechanism, 30 ... Continuously variable transmission (CVT), 30a ... First pulley, 30b ... First 2 pulleys, 30c ... belt, 32 ... input shaft, 34 ... output shaft, 40 ... electronic control device, 50 ... hydraulic control circuit, 60 ... accelerator pedal, 70 ... accelerator sensor, 71 ... vehicle speed sensor, 72 ... crank angle sensor, 73 ... Throttle sensor, 74 ... Rotational speed sensor, 100 ... Internal combustion engine, 101 ... Intake camshaft, 102 ... Intake valve, 103 ... Valve characteristic variable mechanism

Claims (5)

Applied to an internal combustion engine mounted on a vehicle equipped with an automatic transmission and equipped with an air amount metering means for metering the intake air amount, the amount of operation of the accelerator pedal, the vehicle speed, and the gear ratio of the automatic transmission In an internal combustion engine output control device that calculates a target output torque of an engine based on a state and calculates a target drive amount of the air amount metering means based on the target output torque.
When the current value of the gear ratio of the automatic transmission when the input shaft and the output shaft of the automatic transmission are rotating in the same direction is smaller than a predetermined value, the automatic transmission is calculated based on the target output torque. The output control apparatus for an internal combustion engine, wherein the target drive amount is limited to a value equal to or less than a preset upper limit value. 2. The output of the internal combustion engine according to claim 1, wherein the upper limit value is set to a drive amount of the air amount metering means in which the output torque of the engine is reduced by a predetermined ratio with respect to the maximum output torque according to the engine speed. Control device. 3. The internal combustion engine according to claim 2, wherein the output torque of the engine that is smaller by the predetermined ratio is an output torque in a change region when the change amount of the output torque with respect to the change amount of the drive amount is changed from a large region to a small region. Output control device. The output control device for an internal combustion engine according to any one of claims 1 to 3, wherein the air amount metering means is a throttle valve provided in an intake passage of the engine. 4. The variable valve characteristic mechanism according to claim 1, wherein the air amount adjusting means is a valve characteristic variable mechanism that adjusts the intake air amount by changing at least one of a maximum lift amount and a valve opening period of an intake valve of the engine. The output control device for an internal combustion engine according to claim 1.

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