JP6103208B2 - Output control device for internal combustion engine - Google Patents

Description

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

A vehicle having a manual transmission is provided with a clutch between the output shaft of the internal combustion engine and the manual transmission, and the clutch is gradually engaged by the driver when the vehicle starts.
When the vehicle starts, the clutch load torque, which becomes the load torque against the rotation of the output shaft of the internal combustion engine, gradually increases as the clutch engagement proceeds. Therefore, in the clutch engagement process, if the output torque of the internal combustion engine is insufficient due to insufficient accelerator operation by the vehicle driver, engine stall may occur. Therefore, for example, as described in Patent Document 1, in order to automatically compensate for the shortage of output torque at the time of clutch engagement, the engine output assist torque corresponding to the clutch load torque is calculated, and the calculated assist An output control device that performs torque assist control for increasing engine output in accordance with torque has been proposed.

JP 2006-233911 A

Incidentally, in the output control device described in Patent Document 1, the assist torque is updated by adding a predetermined increase permission amount to the assist torque before the update.
Here, if the increase permission amount is excessively increased, the amount of update of the assist torque increases, so that the engine output may change rapidly and the engine rotation speed may be hunted. Therefore, it is necessary to reduce the increase permission amount to some extent. However, if the increase permission amount is reduced, the assist torque update amount is also reduced. In some cases, the increase amount of the engine output is insufficient, and there is a possibility that sufficient torque assist cannot be performed.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an output control device for an internal combustion engine that can appropriately perform torque assist at the time of clutch engagement.

  An output control device for an internal combustion engine that solves the above problem is a device that controls the output of an in-vehicle internal combustion engine whose output shaft is connected to a manual transmission via a clutch. Then, a clutch load torque, which becomes a load torque against the rotation of the output shaft of the internal combustion engine in the clutch engagement process, is calculated every predetermined period, and the assist torque of the engine output is updated based on the calculated clutch load torque. Then, torque assist control for increasing the engine output in accordance with the updated assist torque is performed. The clutch load torque is a torque transmitted to the clutch connected to the output shaft of the engine among the output torque generated in the internal combustion engine, the inertia mass of the internal combustion engine, and the clutch engagement process. It is calculated based on the amount of change in engine speed at

  In this configuration, the clutch load torque is calculated for each predetermined period in the clutch engagement process, the engine output assist torque is updated based on the calculated clutch load torque, and the engine torque is updated according to the updated assist torque. By increasing the output, torque assist during clutch engagement is performed.

  Here, out of the output torque generated in the internal combustion engine, the torque transmitted to the clutch connected to the output shaft of the internal combustion engine is defined as the shaft torque, that is, the auxiliary machine is driven from the output torque generated in the internal combustion engine. The torque excluding the loss of output torque due to the above is the shaft torque. When the clutch is in a released state and the internal combustion engine rotates in a no-load state, the shaft torque that gives rotational torque to the output shaft, the inertia mass of the engine that correlates with the ease of rotation of the internal combustion engine, and the engine rotational speed The relationship of “shaft torque = inertial mass of internal combustion engine × change amount of engine rotational speed” is established. When the clutch starts to be engaged and the clutch load torque starts to increase, the value of “shaft torque” and the value of “inertial mass of internal combustion engine × change amount of engine rotational speed” correspond to the clutch load torque. It will shift by the value. That is, in the clutch engagement process, the relationship “shaft torque−clutch load torque = inertia mass of the internal combustion engine × amount of change in engine rotation speed” is established. Therefore, in this configuration, the clutch load torque is calculated based on the shaft torque, the inertial mass of the internal combustion engine, and the amount of change in the engine rotation speed during the clutch engagement process. The clutch load torque is calculated with high accuracy. For this reason, the engine output assist torque updated based on the clutch load torque can be accurately calculated according to the clutch engagement degree, and torque assist during clutch engagement can be appropriately performed. become able to.

Further, in the output control device, when the calculated clutch load torque is equal to or less than the assist torque before the update, the update mode of the assist torque is changed according to the deviation between the calculated clutch load torque and the assist torque before the update. .

  In a normal clutch engagement process, since the clutch load torque is increasing, the calculated clutch load torque is larger than the assist torque before the update. On the other hand, if the clutch operation is different from normal, such as increasing the amount of depression of the clutch pedal during clutch engagement, the actual clutch load torque will decrease, so the calculated clutch load torque will be updated. May be less than previous assist torque. As described above, when the clutch load torque becomes equal to or less than the assist torque before the update, the boost torque after the update can be suppressed by reducing the assist torque after the update in accordance with the decreased clutch load torque. However, when the updated assist torque is reduced in this way, when the clutch load torque starts to increase again, the response delay of the assist torque becomes significant, and although it is temporary, the assist torque is insufficient and the vehicle starts. May decrease. Therefore, when the decrease in the clutch load torque is a decrease that does not greatly affect the engine speed increase, the updated assist torque is not decreased in accordance with the decreased clutch load torque. By reducing the decrease amount of the assist torque compared to the decrease amount of the clutch load torque, it is possible to suppress the response delay of the assist torque when the clutch load torque starts to increase again, and to improve the startability of the vehicle. it can.

Therefore, in the same configuration, when the calculated clutch load torque is equal to or less than the assist torque before update, according to the deviation between the calculated clutch load torque and the assist torque before update, that is, according to the decrease amount of the clutch load torque. Thus, the update mode of the assist torque is changed, so that the startability of the vehicle when the clutch load torque is temporarily reduced can be improved.

The change of the assist torque update mode is such that when the deviation is larger than the first determination value set in advance, the calculated clutch load torque is set as the updated assist torque, and the deviation is less than or equal to the first determination value. is set to a value smaller than the first determination value that there is the time greater than the second determination value, to set a value obtained by subtracting a predetermined amount from the assist torque before update as an assist torque after the update.

  According to this configuration, when the actual clutch load torque decreases and the difference between the calculated clutch load torque and the assist torque before update becomes larger than the first determination value, the calculated clutch load torque, that is, By setting the reduced clutch load torque as the updated assist torque as it is, it is possible to suppress an increase in the engine speed. In addition, when the actual clutch load torque decreases and the deviation between the calculated clutch load torque and the assist torque before update is less than the first determination value and larger than the second determination value, The assist torque is gradually reduced by setting the value obtained by subtracting a predetermined amount from the assist torque as the updated assist torque. By appropriately setting the predetermined amount for subtraction, the amount of decrease in assist torque can be reduced compared to the amount of decrease in clutch load torque, and as a result, the decreased clutch load torque begins to increase again. The response delay of the assist torque at the time can be suppressed, and the startability of the vehicle can be improved.

In the output control device, when the deviation is equal to or less than the second determination value, it is preferable to set the assist torque before update as the assist torque after update.
When the calculated clutch load torque falls below the assist torque before the update, the deviation between the calculated clutch load torque and the assist torque before the update is slight, and there is almost no effect on the engine speed increase. In the case where there is not, it is more preferable to maintain the assist torque before updating rather than decrease the assist torque in terms of securing the startability of the vehicle. Therefore, in the same configuration, when it can be determined that the deviation between the calculated clutch load torque and the assist torque before the update is not more than the second determination value and sufficiently small, the assist torque before the update is updated. The assist torque is set, that is, the assist torque before the update is substantially maintained. Therefore, the startability of the vehicle can be suitably secured even with this configuration.

  In the output control device, an upper limit value of the assist torque is set based on the engine rotation speed and the accelerator operation amount, and when the updated assist torque is larger than the upper limit value, the upper limit value is set as the updated assist torque. It is preferable to do.

  When the clutch load torque suddenly increases, for example, when the clutch pedal is suddenly operated, the assist torque updated based on the clutch load torque also suddenly increases. Therefore, in some cases, the vehicle acceleration suddenly changes when the clutch is engaged. There is a fear. In this respect, according to the same configuration, the assist torque is regulated by the upper limit value, so that a sudden change in the vehicle acceleration can be suppressed. Here, since the vehicle acceleration at the time of clutch engagement increases as the engine rotational speed increases, the upper limit value of the assist torque is set based on the engine rotational speed in the same configuration. Therefore, a sudden change in vehicle acceleration at the time of clutch engagement can be appropriately suppressed. In this configuration, the upper limit value of the assist torque is set in consideration of not only the engine speed but also the accelerator operation amount. Therefore, it is possible to perform torque assist in accordance with the operation feeling of the vehicle driver. In the same configuration, it is preferable to increase the upper limit as the accelerator operation amount increases.

  Further, as described above, the vehicle acceleration at the time of clutch engagement increases as the engine speed increases. Therefore, the above upper limit value is made smaller as the engine speed is higher, so that a sudden change in vehicle acceleration at the time of clutch engagement caused by a sudden increase in assist torque due to a sudden increase in clutch load torque is suitably suppressed. Can do. Further, since the output torque of the internal combustion engine is small when the engine rotational speed is low, if the upper limit value is decreased in such a low rotational speed range, the assist torque may be insufficient. In this respect, in the same configuration, the upper limit value is increased as the engine rotational speed is lower, so that the shortage of assist torque in the low rotational speed region can be suppressed.

  In the output control device, an accelerator request torque that is a requested output torque of the engine according to an accelerator operation amount is calculated, an added value of the accelerator request torque and the updated assist torque is calculated as a final request torque, and the final It is preferable to output the required torque from the internal combustion engine.

  According to this configuration, since the accelerator operation amount of the vehicle driver is reflected in the engine output torque in the clutch engagement process, it is possible to suppress the occurrence of discomfort with the accelerator operation when executing the torque assist control. it can. For example, when the assist torque is gradually decreased to “0” with complete engagement of the clutch 12, the ratio of the accelerator required torque to the final required torque gradually increases. For this reason, it is possible to suppress a sudden change in output torque or the like when shifting from torque assist control to output torque control corresponding to a normal accelerator operation amount.

  The shaft torque can be detected by a sensor or the like or can be estimated appropriately based on the engine operating state. For example, in estimating the shaft torque, the output torque generated in the internal combustion engine is calculated based on the intake air amount, the engine rotational speed, the ignition timing, and the like. Then, the output torque is estimated by subtracting the load torque caused by driving the auxiliary machine, the load torque corresponding to the viscosity of the lubricating oil, or the torque necessary for maintaining the engine speed at the target idle speed. be able to. In addition, the inertial mass may be obtained through a previous actual machine experiment or may be calculated by simulation or the like.

The schematic diagram which shows the structure in one Embodiment of the output control apparatus of an internal combustion engine. 4 is a flowchart showing a processing procedure for calculating engine shaft torque in the embodiment. 4 is a flowchart showing a series of processing procedures when torque assist control is performed in the embodiment. 4 is a flowchart showing a processing procedure for calculating a base assist torque in the embodiment. 4 is a flowchart showing a processing procedure for calculating an upper limit value of requested assist torque in the embodiment. The graph which shows the relationship between an engine speed and an upper limit. The graph which shows the relationship between the amount of accelerator operation, and an upper limit. 4 is a flowchart showing a processing procedure for calculating a required assist torque in the embodiment. 4 is a flowchart showing a processing procedure for calculating a final value of assist torque in the embodiment. 4 is a flowchart showing a processing procedure for calculating a final required torque in the embodiment. The conceptual diagram which shows the relationship between an accelerator operation amount and vehicle speed, and an accelerator request torque. The conceptual diagram which shows the change by the difference in a gear stage about the relationship between an accelerator operating amount and an accelerator request torque. The timing chart which shows the execution aspect of the torque assist control in the same embodiment.

  Hereinafter, an embodiment of an output control device for an internal combustion engine will be described with reference to FIGS. The output control device of this embodiment is applied to an engine mounted on a vehicle with a manual transmission.

  As shown in FIG. 1, a crankshaft 11 that is an output shaft of the engine 10 is connected to a transmission input shaft 15 that is an input shaft of a manual transmission 14 via a clutch 12. The clutch 12 is released when the driver depresses the clutch pedal 13, and power transmission between the crankshaft 11 and the transmission input shaft 15 is cut off. On the other hand, the clutch 12 shifts to the engaged state as the driver decreases the amount of depression of the clutch pedal 13, and power transmission between the crankshaft 11 and the transmission input shaft 15 is performed.

  In the manual transmission 14, the gear ratio of the drive system of the vehicle is changed by changing the gear position according to the operation of the shift lever 16 by the driver. The manual transmission 14 has six shift speeds, but may be a manual transmission having other shift speeds.

Auxiliary machines such as an air conditioning compressor 30 and an alternator 31 are drivingly connected to the crankshaft 11.
The engine 10 is controlled by the control device 17. The control device 17 receives detection signals such as sensors and switches provided in each part of the vehicle. Examples of such sensors include an air flow meter 20 that detects an intake air amount GA of the engine 10, a crank angle sensor 21 that detects an engine rotational speed NE that is the rotational speed of the engine 10, and a water temperature that detects a cooling water temperature THW of the engine 10. There is a sensor 22 and an accelerator sensor 23 that detects an accelerator operation amount ACCP that is an operation amount of an accelerator pedal. Examples of such sensors include a vehicle speed sensor 24 that detects the vehicle speed SP of the vehicle, and a shift sensor 25 that detects a shift position SFT that is an operation position of the shift lever 16. Further, as a switch or the like, the first clutch switch 26U that detects that the clutch 12 is completely engaged by detecting non-operation of the clutch pedal 13, and the clutch 12 that detects depression of the clutch pedal 13 is detected. There is a second clutch switch 26L for detecting the release. Incidentally, it is also possible to omit the shift sensor 25 and determine the shift position SFT based on the vehicle speed SP and the engine rotational speed NE.

The control device 17 performs various engine controls such as fuel injection control and ignition timing control of the engine 10 based on detection signals of various sensors.
By the way, when the vehicle starts, the clutch 12 is gradually engaged by the driver. As the engagement of the clutch 12 proceeds, the clutch load torque that becomes a load torque against the rotation of the crankshaft 11 gradually increases. Accordingly, if the output torque of the engine 10 is insufficient due to a lack of accelerator operation by the vehicle driver during the engagement process of the clutch 12, an engine stall may occur. Therefore, the control device 17 calculates the clutch load torque for each predetermined period so as to automatically compensate for the shortage of the output torque at the time of clutch engagement, and calculates the assist torque of the engine output based on the calculated clutch load torque. Calculate and update. Then, torque assist control for increasing the engine output according to the updated assist torque is performed.

Hereinafter, torque assist control performed by the control device 17 will be described.
First, calculation processing of the engine shaft torque TE used for torque assist control will be described. The calculation process of the engine shaft torque TE is repeatedly executed by the control device 17 at predetermined intervals. The engine shaft torque TE is the shaft torque that is the torque transmitted to the clutch 12 connected to the crankshaft 11 among the output torque generated in the engine 10, that is, the drive of the auxiliary machine from the output torque of the engine 10. This is a value obtained by smoothing the shaft torque that is the torque excluding the loss of the output torque due to the above.
(Engine shaft torque calculation process)
As shown in FIG. 2, when the calculation process of the engine shaft torque TE is started, it is first determined whether or not the fuel is being cut (S110). When the fuel is not being cut (S110: NO), the output torque TEs generated in the engine 10 is calculated based on the engine operating state (S120). In step S120, the base value of the output torque TEs is calculated based on the intake air amount GA, the engine speed NE, and the like. In order to consider the change in output torque due to the ignition timing, the base value of the output torque TEs is corrected according to the currently set ignition timing, and the base value after the correction is set as the output torque TEs.

  On the other hand, if it is determined in step S110 that the fuel is being cut (S110: YES), the output torque TEs is set to “0” because the combustion of the air-fuel mixture has not occurred in the engine 10 (S130). .

  Next, the basic shaft torque TEb is calculated (S140). The basic shaft torque TEb is the engine shaft torque TE before the annealing process, and can be calculated in an appropriate manner. For example, in this embodiment, it is calculated based on the following formula (1).

TEb = TEs−TEh−TEid (1)
TEb: Basic shaft torque TEb
TEs: Output torque
TEh: Load torque
TEid: Idle learning torque

The load torque TEh is a torque component that decreases until the output torque TEs generated in the engine 10 is transmitted to the clutch 12 connected to the crankshaft 11. For example, the drive torque torque of the compressor 30 and the alternator 31, For example, load torque according to the viscosity of the lubricating oil. The driving load torque of the compressor 30 can be calculated based on the refrigerant pressure of the air conditioner, and the driving load torque of the alternator 31 can be calculated based on the power generation amount of the alternator 31. Further, the load torque according to the viscosity of the lubricating oil can be calculated based on the cooling water temperature THW, the oil temperature of the lubricating oil, and the like.

  The idle learning torque TEid is a torque necessary for maintaining the engine rotational speed NE of the engine 10 at the target idle rotational speed. The idle learning torque TEid is a value having a certain value of the actual value of the load torque TEh. Reflected. For example, if the actual load torque TEh is high, the idle learning torque TEid is relatively high, and if the actual load torque TEh is low, the idle learning torque TEid is relatively small. By adding such idle learning torque TEid, it is possible to suppress the influence of the estimation error of the load torque TEh, which is the estimated torque, on the calculation of the basic shaft torque TEb.

  Next, it is determined based on the accelerator operation amount ACCP or the like whether the accelerator pedal is “ON”, that is, whether or not the accelerator pedal is operated (S150). When the accelerator pedal is “ON” (S150: YES), the first coefficient KN1 is set as the smoothing coefficient KN when the basic shaft torque TEb is smoothed (S160).

  On the other hand, when the accelerator pedal is not “ON” and the accelerator pedal is not operated (S150: NO), the second coefficient KN2 is set as the smoothing coefficient KN when the basic shaft torque TEb is smoothed. (S170).

  The first coefficient KN1 is set so that the degree of smoothing of the basic shaft torque TEb by the annealing process is smaller than the second coefficient KN2. That is, the responsiveness of the engine shaft torque TE after the annealing process to the basic shaft torque TEb before the annealing process is higher in the annealing process using the first coefficient KN1 than in the annealing process using the second coefficient KN2. In addition, the first coefficient KN1 and the second coefficient KN2 are respectively set. The reason for changing the smoothing coefficient KN according to the operation state of the accelerator pedal is as follows.

  That is, when the accelerator pedal is operated, the output torque generated from the engine 10 is larger than when the accelerator pedal is not operated, so that the actual change in shaft torque is accelerated. Therefore, the smoothing coefficient KN is changed so that the smoothing degree of the basic shaft torque TEb by the smoothing process is smaller when the accelerator pedal is not operated than when the accelerator pedal is not operated. Accordingly, the responsiveness of the engine shaft torque TE after the smoothing process to the basic shaft torque TEb before the smoothing process is higher when the accelerator pedal is not operated, and when the accelerator pedal is operated, the response is not Compared with the operation, the engine shaft torque TE, which is the smoothed value of the basic shaft torque TEb, changes quickly. Therefore, compared with the case where the smoothing degree of the basic shaft torque TEb is the same between when the accelerator pedal is not operated and when the accelerator pedal is operated, the change in the smoothing value of the basic shaft torque TEb is a change in the actual shaft torque. Get closer.

When the smoothing coefficient KN is set in this way, the basic shaft torque TEb is smoothed using the set smoothing coefficient KN, and the basic shaft torque TEb after the smoothing process is used as the engine shaft torque TE. After the calculation (S180), this process is temporarily terminated.
(Torque assist control)
FIG. 3 shows a series of processing procedures for performing torque assist control. 4 to 12 show details of a series of processing procedures for performing torque assist control. A series of processing procedures shown in FIG. 3 is repeatedly executed by the control device 17 at predetermined intervals.

  As shown in FIG. 3, first, the control device 17 calculates a base assist torque ATb, which is a basic value of the assist torque (S1000: refer to FIG. 4 for details of the processing contents).

Once the base assist torque ATb is calculated, the assist torque upper limit value ATmax is calculated (S2000: see FIGS. 5 to 7 for details of the processing contents).
Once the upper limit value ATmax is calculated, next, the required assist torque ATD, which is the previous stage torque for calculating the assist torque AT, is calculated (S3000: see FIG. 8 for details of the processing contents). ).

  Once the requested assist torque ATD calculation process is performed, an assist torque AT (assist torque final value) calculation process is then performed (S4000: refer to FIG. 9 for details of the process contents).

  Once the assist torque AT is calculated, the final required torque TF, which is the final torque required for the engine 10, is then calculated (S5000: see FIGS. 10 to 12 for details of the processing contents). ). And a series of these processes is once ended.

Next, each process will be described in detail.
(Base assist torque calculation process)
As shown in FIG. 4, when this calculation process is started, it is first determined whether or not the joining flag is “ON” (S1010).

  This engagement flag is a flag indicating whether or not the clutch 12 is in the engagement process when the vehicle starts, that is, whether or not the clutch 12 is in the half engagement state to the complete engagement state. Is set to "ON". Further, when the clutch 12 is in the released state, it is set to “OFF”. When it is confirmed that the clutch 12 has shifted from the half-clutch state to the fully engaged state, the clutch 12 is changed from “ON” to “OFF”.

  The setting of the joint flag indicating the state of the clutch 12 may be performed in an appropriate manner. For example, a sensor that measures the stroke amount of the clutch pedal 13 can be provided, and the state of the clutch 12 can be determined based on the measured stroke amount. A sensor for measuring the rotational speed of the transmission input shaft 15 is also provided. When the measured rotation speed is “0”, it is determined that the clutch 12 is in a released state. Further, when the measured rotational speed is the same as the engine rotational speed of the engine 10 in operation, it is determined that the clutch 12 is in the fully engaged state. When the measured rotational speed is higher than “0” and lower than the engine rotational speed of the operating engine 10, it can be determined that the clutch 12 is in the engagement process. Further, in the engagement process of the clutch 12, since the amount of change in the engine speed is small, it is determined that the clutch 12 is in the engagement process when the amount of change is lower than a predetermined threshold. Is also possible.

  In step S1010, when the joining flag is “OFF” (S1010: NO), “0” is set to the base assist torque ATb (S1110), and this process is terminated.

  On the other hand, when it is determined in step S1010 that the joining flag is “ON” (S1010: YES), the clutch load torque CL is calculated (S1020). This clutch load torque CL is calculated based on the following equation (2).

CL = TE− (EW × ΔNE) (2)
CL: Clutch load torque TE: Engine shaft torque EW: Inertial mass of engine 10 ΔNE: Speed change amount = Change amount per unit time of engine rotational speed NE

Note that the inertial mass EW is a value that correlates with the ease of rotation of the engine 10, and can be obtained through a previous actual machine experiment or can be calculated by simulation or the like. Further, the speed change amount ΔNE is a change amount per unit time of the engine speed NE.

  Next, the currently set base assist torque ATb, that is, the base assist torque ATb set when this processing was executed in the previous execution cycle, in other words, before being updated in the current execution cycle. It is determined whether or not the clutch load torque CL calculated in step S1020 is larger than the base assist torque ATb (S1030).

  When the calculated clutch load torque CL is larger than the base assist torque ATb before the update (S1030: YES), the clutch load torque CL calculated in step S1020 is set as the base assist torque ATb, whereby the base assist torque is set. The ATb is updated (S1070), and this process ends. When the base assist torque ATb is updated in step S1070, since an affirmative determination is made in step S1030, the updated base assist torque ATb is larger than that before the update.

  On the other hand, when the calculated clutch load torque CL is equal to or lower than the base assist torque ATb before update (S1030: NO), the torque deviation obtained by subtracting the clutch load torque CL calculated in step S1020 from the base assist torque ATb before update. ΔT is calculated (S1040).

  Then, it is determined whether or not the torque deviation ΔT is larger than the first determination value H1 (S1050). As the first determination value H1, the clutch load torque CL calculated this time is small with respect to the base assist torque ATb before the update, and it can be determined that there is a possibility that the engine rotational speed will be increased if it remains as it is. A torque deviation ΔT is set.

  When the torque deviation ΔT is larger than the first determination value H1 (S1050: YES), the base load assist torque ATb is updated by setting the clutch load torque CL calculated in step S1020 as the base assist torque ATb ( S1080), this processing is terminated. When the base assist torque ATb is updated in step S1080, a negative determination is made in step S1030. Therefore, the updated base assist torque ATb is smaller than that before the update.

  When it is determined in step S1050 that the torque deviation ΔT is equal to or smaller than the first determination value H1 (S1050: NO), it is determined whether the torque deviation ΔT is larger than the second determination value H2 (S1060). . The second determination value H2 is set to a value smaller than the first determination value H1. As the second determination value H2, although the clutch load torque CL calculated this time is small with respect to the base assist torque ATb before the update, the torque deviation ΔT is small and has an influence on the engine speed increase. A torque deviation ΔT that can be determined to be almost absent is set.

  When the torque deviation ΔT is larger than the second determination value H2 (S1060: YES), a value obtained by subtracting a predetermined constant K1 from the base assist torque ATb before update is set as the base assist torque ATb after update (S1090). This process is terminated. The constant K1 is a value smaller than the second determination value H2, and the value is set so that the updated base assist torque ATb does not decrease significantly compared to before the update.

  When it is determined in step S1060 that the torque deviation ΔT is equal to or smaller than the second determination value H2 (S1060: NO), the base assist torque ATb before the update is set as the base assist torque ATb after the update, that is, the current The set base assist torque ATb is held (S1100), and this process is terminated.

When the calculation process of the base assist torque ATb is completed in this way, the calculation process of the upper limit value ATmax of the assist torque is then performed.
(Calculation processing of upper limit value of assist torque)
As shown in FIG. 5, when this calculation process is started, it is first determined whether the accelerator pedal is “ON”, that is, whether the accelerator pedal is being operated based on the accelerator operation amount ACCP ( S2010). When the accelerator pedal is “ON” (S2010: YES), the upper limit value ATmax is set based on the engine speed NE and the accelerator operation amount ACCP.

As shown in FIG. 6, the upper limit value ATmax is made smaller as the engine speed NE is higher.
As shown in FIG. 7, the upper limit value ATmax is increased as the accelerator operation amount ACCP is larger.

  On the other hand, when the accelerator pedal is not “ON” (S2010: NO), upper limit value ATmax is set based on engine speed NE (S2030). Also in setting the upper limit value ATmax in step S2030, as shown in FIG. 6, the upper limit value ATmax is made smaller as the engine speed NE is higher.

When the calculation process of the upper limit value ATmax is completed in this way, the calculation process of the requested assist torque is performed next.
(Request assist torque calculation process)
As shown in FIG. 8, when this calculation process is started, it is first determined whether or not the above-described joining flag is “ON” (S3010).

When the joining flag is “OFF” (S3010: NO), “0” is set to the requested assist torque ATD (S3040), and this process is terminated.
On the other hand, when it is determined in step S3010 that the engagement flag is “ON” (S3010: YES), it is next determined whether or not the clutch 12 is completely engaged (S3020). What is necessary is just to perform the process which determines this complete joining suitably. For example, when complete engagement of the clutch 12 by the first clutch switch 26U is continuously detected for a certain period of time, it can be determined that the clutch 12 is fully engaged. Further, when a sensor for measuring the stroke amount of the clutch pedal 13 is provided, the clutch 12 is fully engaged when the stroke amount when the clutch 12 is completely engaged is detected for a certain period of time. It can be determined that they match. When a sensor for measuring the rotational speed of the transmission input shaft 15 is provided, the measured rotational speed matches the engine rotational speed NE of the engine 10 that is in operation, and one of them. It can be determined that the clutch 12 is completely engaged when the engaged state has continued to some extent.

  When the clutch 12 is not completely engaged (S3020: NO), it is determined that the clutch 12 is in the engagement process. Then, the smaller one of the base assist torque ATb updated in the above-described base assist torque calculation process and the upper limit value ATmax calculated in the above-described upper limit calculation process is set as the required assist torque ATD. (S3050), this process is terminated.

  On the other hand, when it is determined in step S3020 that the clutch 12 is completely engaged (S3020: YES), it is determined whether the accelerator pedal is “ON”, that is, whether the accelerator pedal is operated. Determination is made based on the amount ACCP or the like (S3030). When the accelerator pedal is “ON” (S3030: YES), it is determined that the assist torque is unnecessary because the clutch 12 is completely engaged and the accelerator pedal is operated, and the requested assist is determined. The torque ATD is set to “0” (S3040). Then, this process ends.

  On the other hand, when it is determined in step S3030 that the accelerator pedal is not “ON” (S3030: NO), the accelerator pedal is not operated and the engine 10 is in the idling state. In this way, when the clutch 12 is fully engaged while the engine 10 is in the idling operation state, the vehicle is caused to travel with the output torque of the engine 10 in the idling operation state, that is, pseudo creep running is realized. Therefore, the required assist torque ATD is calculated based on the target idle rotational speed NEp (S3060). In step 3060, the required assist torque ATD is increased as the target idle speed NEp is higher. Then, this process ends.

When the calculation processing of the required assist torque ATD is completed in this way, the calculation processing of the assist torque AT is performed next.
(Assist torque calculation process)
As shown in FIG. 9, when this calculation process is started, first, it is determined whether or not the above-described joining flag is “ON” (S4010).

When the joining flag is “OFF” (S4010: NO), “0” is set to the assist torque AT (S4100).
On the other hand, when it is determined in step S4010 that the engagement flag is “ON” (S4010: YES), it is next determined whether or not the clutch 12 is completely engaged (S4020). The determination in step S4020 is the same as the determination in step S3020.

  When the clutch 12 is not completely engaged (S4020: NO), it is determined that the clutch 12 is in the engagement process. Then, the required assist torque ATD calculated in the above-described required assist torque calculation process is set as the assist torque AT (S4110).

  On the other hand, when it is determined in step S4020 that the clutch 12 is completely engaged (S4020: YES), processing for gradually decreasing the assist torque AT is sequentially performed. By performing such a gradual change process, a sudden change in the output torque of the engine 10 can be suppressed as compared with a case where the assist torque AT is suddenly reduced when the clutch 12 is completely engaged. First, it is determined whether or not the actual state of the clutch 12 is a released state (S4030). In this step S4030, an affirmative determination is made when the release of the clutch 12 is detected by the second clutch switch 26L.

  Here, when the process of step S4030 is performed, it is determined in step S4020 that the clutch 12 is completely engaged. Therefore, if it is normal, negative determination is made in step S4030.

  However, since the complete engagement determination in step S4020 is performed at a predetermined execution cycle, if the actual state of the clutch 12 is released during the execution cycle, the complete engagement determination is performed. Until it is correctly updated, the determination result of complete engagement and the actual state of the clutch 12 become different. Therefore, in the present embodiment, the sampling cycle of the second clutch switch 26L is made shorter than the complete engagement determination cycle so that the released state of the clutch 12 can be grasped earlier. If the affirmative determination is made in step S4030 even though the affirmative determination is made in step S4020, the clutch 12 of the clutch 12 by the second clutch switch 26L is determined rather than the state determination of the clutch 12 by the complete engagement determination process. Prioritizing the state determination, the assist torque AT is reduced on the assumption that the clutch 12 is in the released state.

  That is, when the clutch 12 is in the disengaged state, the clutch load torque CL is substantially “0”, and therefore the engine speed may increase unless the assist torque AT is reduced early. Further, when the clutch 12 that has been released is re-engaged, if the assist torque AT remains at a relatively large torque, the vehicle acceleration increases abruptly and a longitudinal shock occurs in the vehicle. There is also a fear. Therefore, when it is determined in step S4030 that the actual state of the clutch 12 is the released state (S4030: YES), a relatively large value is used as the gradually changing value J when the assist torque AT is gradually decreased. The set first gradually changing value J1 is set (S4050). When the clutch 12 is released, the engine 10 and the drive system of the vehicle are disconnected, so that even if the assist torque AT is greatly reduced, the vehicle is less likely to be shocked.

  On the other hand, when it is determined in step S4030 that the actual state of the clutch 12 is not a released state (S4030: NO), as a process for gradually decreasing the assist torque as the clutch 12 is completely engaged, Steps S4050 to S4090 and step S4120 are sequentially performed.

  In step S4050, it is determined based on the accelerator operation amount ACCP or the like whether the accelerator pedal is “OFF”, that is, whether or not the accelerator pedal is operated. When the accelerator pedal is “OFF” (S4050: YES), a value that is considerably smaller than the first gradual change value J1 is set as the gradual change value J for gradually decreasing the assist torque AT. The third gradually changing value J3 is set (S4060).

  On the other hand, when the accelerator pedal is “ON” and the driver is operating the accelerator pedal (S4050: NO), the assist torque is reduced early within a range that does not cause a shock to the vehicle. It is desirable to realize the output request early. Therefore, when a negative determination is made in step S4050, the second gradual change value J2 in which a value slightly larger than the third gradual change value J3 is set as the gradual change value J when the assist torque AT is gradually decreased. Is set (S4070).

  When the gradual change value J is set by any one of the above steps S4050, S4060, and S4070, the gradual change assist torque ATJ is calculated (S4080). The gradually changed assist torque ATJ is the currently set assist torque AT, that is, the assist torque AT set when this process is executed in the previous execution cycle, in other words, in the current execution cycle. This is a value obtained by subtracting the gradual change value J from the assist torque AT before being updated.

  Next, it is determined whether the required assist torque ATD calculated by the above-described required assist torque calculation process is larger than the gradually changed assist torque ATJ calculated in step S4080 (S4090).

  When the required assist torque ATD is larger than the gradually changed assist torque ATJ (S4090: YES), the required assist torque ATD is set as the assist torque AT (S4110).

  On the other hand, when the required assist torque ATD is equal to or lower than the gradually changed assist torque ATJ (S4090: NO), the gradually changed assist torque ATJ is set as the assist torque AT (S4120).

  If “0” is set as the required assist torque ATD when the clutch 12 is fully engaged and the process of step S3040 shown in FIG. 8 is executed, the process proceeds to step S4090. Negative decision. Further, as the requested assist torque ATD when the clutch 12 is completely engaged, the value calculated based on the target idle speed NEp is obtained by executing the process of step S3060 shown in FIG. If it has been set, a negative determination is made in step S 4090 until the assist torque ATJ after gradual change decreases to the calculated value. Therefore, the assist torque ATJ after the gradual change is basically set as the assist torque AT during the execution of the torque assist control and after the clutch 12 is completely engaged.

  When the assist torque AT is set by any one of the steps S4100, S4110, and S4120, a zero guard process for the assist torque AT is executed (S4130). In this zero guard process, when the assist torque AT set by any one of the steps S4100, S4110, and S4120 is a value smaller than “0”, that is, a negative value, the assist torque AT is “0”. "Is set. By executing the zero guard process, the assist torque AT is reset to “0” when the assist torque AT calculated before the zero guard process is erroneously negative for some reason. Is done. Then, this process ends.

When the calculation of the assist torque AT is thus completed and the update of the assist torque AT is completed, a process for calculating the final required torque TF is then performed.
(Calculation process of final required torque)
As shown in FIG. 10, when this calculation process is started, first, the accelerator required torque ACCT is calculated based on the shift position SFT, the vehicle speed SP, and the accelerator operation amount ACCP (S5010). The accelerator required torque ACCP is basically a required output torque to the engine 10 according to the accelerator operation amount ACCP of the vehicle driver.

  As shown in FIG. 11, accelerator request torque ACCT is set to a larger value as accelerator operation amount ACCP is larger. Further, the accelerator required torque ACCT is set to a larger value as the vehicle speed SP is higher.

  As shown in FIG. 12, the setting of the accelerator required torque ACCT based on the accelerator operation amount ACCP is also changed by the gear position of the manual transmission 14. That is, the accelerator operation amount ACCP corresponding to the same accelerator required torque ACCT becomes smaller as the shift speed increases in the order of 1st speed, 2nd speed, 3rd speed, 4th speed, 5th speed, and 6th speed. . As a result of such a variable speed setting, the higher the shift speed, the smaller the accelerator operation amount ACCP corresponding to the same accelerator required torque ACCT. Thus, the higher the shift speed, the higher the accelerator request torque with a smaller accelerator operation amount ACCP. An ACCT can be requested.

  When the accelerator required torque ACCT is calculated in step S5010, in step S5020, a final required torque TF that is a required value of the output torque of the engine 10 is calculated, and this process is terminated. The final required torque TF is calculated by adding the accelerator required torque ACCT calculated in step S5010 and the updated assist torque AT calculated in the assist torque calculation process described above. Then, the output control of the engine 10 is performed so that the output torque of the engine 10 becomes the final required torque TF.

FIG. 13 shows an example of torque control by torque assist control in the present embodiment that is performed at the time of clutch engagement when the vehicle starts.
As shown in FIG. 13, when the accelerator pedal is operated at time t1, the accelerator required torque ACCT corresponding to the accelerator operation amount ACCP is calculated after time t1.

  Since the calculated assist torque AT is “0” before the engagement of the clutch 12 is started at time t2, the final required torque TF is the same as the accelerator required torque ACCT.

  When the engagement of the clutch 12 is started at time t2, the assist torque AT is calculated based on the clutch load torque CL or the like, and the final required torque TF is the difference between the accelerator required torque ACCT and the assist torque AT. It becomes the total value.

  If the calculated base assist torque ATb (shown by a one-dot chain line) exceeds the upper limit value ATmax between time t3 and time t4, the required assist torque ATD is limited to the upper limit value ATmax (step S3050 above). Processing). Therefore, between time t3 and time t4, the assist torque AT is set to a value smaller than the base assist torque ATb.

  When the clutch 12 is completely engaged at time t4, the base assist torque ATb is set to “0” (the process in step S1110). Thereby, the feeling of the vehicle popping out when the complete engagement of the clutch 12 is completed is reduced. However, if the “0” setting of the base assist torque ATb is reflected in the assist torque AT as it is, the output torque of the engine 10 may be drastically reduced and the behavior of the vehicle may be disturbed. In this regard, in the present embodiment, when it is determined that the clutch 12 is completely engaged, the assist torque AT is gradually reduced by the gradual change value J (the process of step S4080). Therefore, when the assist torque AT is decreased with the complete engagement of the clutch 12, a sudden change in the output torque of the engine 10 can be suppressed.

  The assist torque AT is gradually reduced by complete engagement of the clutch 12, and when the assist torque AT becomes “0” at time t5, the final required torque TF after the time t5 is the same as the accelerator required torque ACCT. become.

  Incidentally, although not shown in FIG. 13, when the accelerator pedal is not operated after time t4, the accelerator required torque ACCT is set to “0”, and the target idle rotation is performed by the process of step S3060. The required assist torque ATD is set based on the speed NEp. As described above, when the required assist torque ATD based on the target idle rotational speed NEp is set as the required assist torque ATD when the clutch 12 is completely engaged, the gradually changed assist torque ATJ is set. Is negative in step S4090 until the required assist torque ATD set based on the target idle rotation speed NEp decreases. When the gradually changed assist torque ATJ is reduced to the required assist torque ATD set based on the target idle rotational speed NEp, an affirmative determination is made in step S4090, and in step S4110, based on the target idle rotational speed NEp. The set required assist torque ATD is set as the assist torque AT. Accordingly, the final required torque TF after the time t5 becomes the same value as the required assist torque ATD set based on the target idle speed NEp, whereby the output torque of the engine 10 is an output required for pseudo creep travel. It is controlled to be torque.

Next, the operation of the torque assist control described above will be described.
When the clutch 12 is in a disengaged state and the engine 10 rotates in a no-load state, the shaft torque that gives rotational torque to the crankshaft 11, the inertia mass EW that correlates with the ease of rotation of the engine 10, and the speed change The relationship of “shaft torque = inertia mass EW × speed change amount ΔNE” is established between the amount ΔNE and the amount ΔNE. When the clutch 12 starts to be engaged and the clutch load torque starts to increase, the value of “shaft torque” and the value of “inertial mass EW × speed change amount ΔNE” are a value corresponding to the clutch load torque. Will only shift. That is, in the engagement process of the clutch 12, the relationship of “shaft torque−clutch load torque = inertia mass EW × speed change amount ΔNE” is established. Therefore, as shown in the above formula (2), in the present embodiment, the clutch load torque CL is calculated based on the engine shaft torque TE, the inertial mass EW, and the speed change amount ΔNE in the clutch engagement process. In this way, the clutch load torque CL in the clutch engagement process is accurately calculated. Therefore, since the base assist torque ATb of the assist torque updated based on the clutch load torque CL is also calculated accurately according to the degree of engagement of the clutch 12 in the processing of Step S1070 and Step S1080, the clutch engagement Torque assist can be performed appropriately.

  Further, when it is determined in step S1030 that the calculated clutch load torque CL is greater than the base assist torque ATb before update, in step S1030, the base assist torque ATb after update of the calculated clutch load torque CL is determined. I am trying to set it as Accordingly, the base assist torque ATb is increased as the clutch 12 is engaged and the clutch load torque CL is increased, so that the engine output is appropriately increased in the clutch engagement process. become.

  By the way, in the normal clutch engagement process, since the actual clutch load torque is increasing, the calculated clutch load torque CL is the base assist torque ATb before the update (that is, the clutch calculated in the previous calculation cycle). It becomes larger than the base assist torque ATb) set based on the load torque CL. On the other hand, when the clutch operation different from the normal operation such as increasing the depression amount of the clutch pedal 13 is performed during the engagement of the clutch 12, the actual clutch load torque decreases, so the calculated clutch load torque CL may be equal to or lower than the base assist torque ATb before update. Thus, when the clutch load torque CL becomes equal to or lower than the base assist torque before update, the base assist torque ATb after update is also reduced in accordance with the decreased clutch load torque CL, thereby suppressing the engine speed increase and the like. be able to. However, if the updated base assist torque ATb is made smaller than before the update, when the clutch load torque CL starts to increase again, the response delay of the base assist torque ATb becomes remarkable, which is temporary, There is a fear that the assist torque AT is insufficient and the startability of the vehicle is lowered. Therefore, when the decrease in the clutch load torque CL is a decrease that does not significantly affect the engine speed increase, the updated base assist torque ATb is also decreased in accordance with the decreased clutch load torque CL. Instead, the reduction amount of the base assist torque ATb is made smaller than the reduction amount of the clutch load torque CL. As a result, a delay in response to the increase side of the base assist torque ATb when the clutch load torque CL starts to increase again can be suppressed, and the startability of the vehicle can be improved.

  Therefore, in this embodiment, when it is determined in step S1030 that the calculated clutch load torque CL is equal to or lower than the base assist torque ATb before the update, the clutch load calculated as the base assist torque ATb before the update is calculated. The update mode of the base assist torque ATb is changed according to the torque deviation ΔT that is a deviation from the torque CL. Since the base assist torque ATb before the update is calculated based on the clutch load torque CL calculated in the previous calculation cycle, the torque deviation ΔT is equal to the clutch load torque CL calculated in the previous calculation cycle. This is a value indicating how much the clutch load torque CL calculated in the current calculation cycle is decreasing. Therefore, the process of changing the update mode of the base assist torque ATb according to the torque deviation ΔT is the same as the process of changing the update mode of the base assist torque ATb according to the amount of decrease in the clutch load torque CL. The startability of the vehicle when the load torque CL temporarily decreases can be enhanced.

  Based on this technical idea, in the present embodiment, in the engagement process of the clutch 12, the actual clutch load torque decreases, and the torque that is the deviation between the calculated clutch load torque CL and the base assist torque ATb before the update. When the deviation ΔT is larger than the first determination value H1, an affirmative determination is made in step S1050. Then, by performing the process of step S1080, the clutch load torque CL calculated in the current calculation cycle, that is, the decreased clutch load torque CL is set as it is as the updated base assist torque ATb. As a result, the updated base assist torque ATb is also reduced in accordance with the reduced clutch load torque CL, so that it is possible to suppress an increase in the engine speed.

  Further, when the actual clutch load torque decreases and the torque deviation ΔT is equal to or less than the first determination value H1 and greater than the second determination value H2, an affirmative determination is made in step S1060. Then, by performing the process of step S1090, a value obtained by subtracting the constant K1 from the base assist torque ATb before update is set as the base assist torque ATb after update, so that the base assist torque ATb gradually increases. It will be made smaller. Therefore, the decrease amount of the base assist torque ATb can be reduced compared with the decrease amount of the clutch load torque CL, whereby the base assist torque ATb increases when the decreased clutch load torque CL begins to increase again. Response delay to the vehicle can be suppressed, and the startability of the vehicle can be improved.

  Further, when the calculated clutch load torque CL is equal to or lower than the base assist torque ATb before the update, when the torque deviation ΔT is slight and there is almost no influence on the engine speed increase, the base assist torque ATb is set. It is more preferable to maintain the base assist torque ATb before the update, in order to ensure the startability of the vehicle. Therefore, in this embodiment, when a negative determination is made in step S1060, that is, when it can be determined that the torque deviation ΔT is equal to or less than the second determination value H2 and is sufficiently small, in step S1100, before the update. The base assist torque ATb is set as the updated base assist torque ATb. That is, the base assist torque ATb before the update is substantially maintained. Accordingly, since the decrease in the base assist torque ATb can also be suppressed by this, the response delay toward the increase side of the base assist torque ATb when the decreased clutch load torque CL starts to increase again can be suppressed. The startability can be suitably secured.

  Further, when the clutch load torque CL increases rapidly, for example, when the clutch pedal 13 is suddenly operated, the base assist torque ATb updated based on the clutch load torque CL also increases rapidly. Therefore, if the increased base assist torque ATb is set to the required assist torque ATD as it is, the vehicle acceleration may change suddenly when the clutch is engaged. In this regard, in the present embodiment, since the required assist torque ATD is limited by the above-described upper limit value ATmax in step S3050, such a sudden change in vehicle acceleration can be suppressed.

  Here, since the vehicle acceleration at the time of clutch engagement increases as the engine rotational speed NE increases, the upper limit value ATmax is variably set based on the engine rotational speed NE. More specifically, as shown in FIG. 6, the upper limit value ATmax is made smaller as the engine speed NE is higher. Therefore, a sudden change in the vehicle acceleration at the time of clutch engagement due to a sudden increase in the required assist torque ATD due to a sudden increase in the clutch load torque CL can be suitably suppressed. Since the output torque of the engine 10 is small when the engine rotational speed NE is low, if the upper limit value ATmax is decreased in such a low rotational speed range, the required assist torque ATD may be insufficient. In this regard, in the present embodiment, since the upper limit value ATmax is set according to the engine rotational speed NE in the above-described manner, the upper limit value ATmax is increased as the engine rotational speed NE is lower. Therefore, the shortage of the required assist torque ATD in the low rotation speed region can be suppressed.

  In setting the upper limit value ATmax, not only the engine speed NE but also the accelerator operation amount ACCP is considered. More specifically, as shown in FIG. 7, the upper limit value ATmax is increased as the accelerator operation amount ACCP is larger. Accordingly, as the accelerator operation amount ACCP is larger, the required assist torque ATD is more difficult to be limited by the upper limit value ATmax. Further, even when the requested assist torque ATD is limited by the upper limit value ATmax, the requested assist torque ATD after the limitation becomes larger as the accelerator operation amount ACCP is larger. Therefore, it is possible to perform torque assist in accordance with the operation feeling of the vehicle driver.

  In step S5010, an accelerator required torque ACCT, which is a required output torque of the engine 10 according to the accelerator operation amount ACCP, is calculated. In step S5020, the calculated accelerator required torque ACCT and the updated assist torque are calculated. The added value with AT is calculated as the final required torque TF. The calculated final required torque TF is output from the engine 10. As described above, since the final required torque TF includes the accelerator required torque ACCT, the accelerator operation amount ACCP of the vehicle driver can be reflected in the output torque of the engine 10 in the clutch engagement process. Therefore, when torque assist control is executed, it is possible to suppress the occurrence of an uncomfortable feeling of output torque with respect to the accelerator operation. In the present embodiment, the assist torque AT is gradually decreased toward “0” with the complete engagement of the clutch 12. Therefore, in the process of decreasing the assist torque AT, the ratio of the assist torque AT to the final required torque TF is gradually decreased, while the ratio of the accelerator required torque ACCT is gradually increased. For this reason, it is possible to suppress an abrupt change in output torque or the like when shifting from torque assist control to output torque control corresponding to a normal accelerator operation.

As described above, according to the present embodiment, the following effects can be obtained.
(1) Based on the engine shaft torque TE, the inertia mass EW of the engine 10 and the speed change amount ΔNE of the engine rotation speed in the clutch engagement process, the clutch load torque CL is calculated using the above equation (2). Therefore, the clutch load torque CL in the clutch engagement process can be calculated with high accuracy. Therefore, the base assist torque ATb that is updated based on the clutch load torque CL can be accurately calculated according to the engagement degree of the clutch 12, and torque assist at the time of clutch engagement is appropriately performed. Will be able to.

  (2) When the calculated clutch load torque CL is larger than the base assist torque ATb before update, the calculated clutch load torque CL is set as the base assist torque ATb after update. Accordingly, the engine output can be appropriately increased in the clutch engagement process.

  (3) When the calculated clutch load torque CL is equal to or less than the base assist torque ATb before update and the clutch load torque CL is decreasing, the calculated clutch load torque CL and the base assist torque ATb before update are The update mode of the base assist torque ATb is changed according to the torque deviation ΔT.

  More specifically, when the torque deviation ΔT is larger than the first determination value H1, the calculated clutch load torque CL is set as the updated base assist torque ATb. As a result, even when an operation for reducing the actual clutch load torque is performed during the engagement of the clutch 12, it is possible to suppress the engine rotational speed from rising.

  When the torque deviation ΔT is equal to or less than the first determination value H1 and greater than the second determination value H2 set to a value smaller than the first determination value H1, the constant K1 is calculated from the base assist torque ATb before the update. Is set as the updated base assist torque ATb. Accordingly, it is possible to suppress a delay in response to the increase side of the base assist torque ATb when the reduced clutch load torque CL starts to increase again, and to improve the startability of the vehicle.

  (4) When the torque deviation ΔT is equal to or less than the second determination value H2 and the decrease amount of the clutch load torque CL is slight, the base assist torque ATb before update is set as the base assist torque ATb after update. It is set. Therefore, even with such an update mode, it is possible to suppress a delay in response to the increase side of the base assist torque ATb when the reduced clutch load torque CL starts to increase again, and to appropriately ensure the startability of the vehicle. become able to.

  (5) When the clutch load torque CL increases rapidly, for example, when the clutch pedal 13 is operated suddenly, the base assist torque ATb updated based on the clutch load torque CL also increases rapidly. Therefore, if the increased base assist torque ATb is set to the required assist torque ATD as it is, the vehicle acceleration may change suddenly when the clutch is engaged. Therefore, the upper limit value ATmax is set based on the engine speed NE and the accelerator operation amount ACCP, and when the updated base assist torque ATb is larger than the upper limit value ATmax, the upper limit value ATmax is set as the updated required assist torque ATD. Like to do. Since the required assist torque ATD is regulated by the upper limit value ATmax in this way, such a sudden change in the vehicle acceleration can be suppressed.

  (6) Since the vehicle acceleration when the clutch is engaged increases as the engine speed increases, the upper limit value ATmax decreases as the engine speed NE increases. Therefore, a sudden change in vehicle acceleration at the time of clutch engagement due to a sudden increase in required assist torque ATD due to a sudden increase in clutch load torque CL can be more suitably suppressed. Further, since the upper limit value ATmax is increased as the engine rotational speed NE is lower, it is possible to suppress the shortage of the required assist torque ATD in the low rotational speed range.

  (7) The upper limit value ATmax is set in consideration of not only the engine speed NE but also the accelerator operation amount ACCP. Therefore, it is possible to perform torque assist in accordance with the operation feeling of the vehicle driver.

  (8) An accelerator request torque ACCT that is a required output torque of the engine 10 according to the accelerator operation amount ACCP is calculated, and an added value of the accelerator request torque ACCT and the updated assist torque AT is calculated as a final request torque TF. The final required torque TF is output from the engine 10. Therefore, it is possible to suppress the occurrence of uncomfortable feeling with respect to the accelerator operation when the torque assist control is executed. In addition, it is possible to suppress a sudden change in output torque or the like when shifting from torque assist control to output torque control corresponding to a normal accelerator operation amount.

In addition, the said embodiment can also be changed and implemented as follows.
In the above embodiment, when calculating the assist torque AT, various torques related to the assist torque AT are calculated, but more simply, the base assist torque ATb is updated based on the clutch load torque CL. The updated base assist torque ATb may be set as the assist torque AT. That is, the assist torque AT may be set directly based on the clutch load torque CL. Even in this case, the effect described in (1) above can be obtained.

  The two determination values, the first determination value H1 and the second determination value H2, are set as comparison values for the torque deviation ΔT. In addition, a determination value may be further set between the first determination value H1 and the second determination value H2, and one or more constants different from the constant K1 may be set. In this case, the response delay toward the increase side of the base assist torque ATb when the clutch load torque CL decreased during the engagement of the clutch 12 starts to increase again can be suppressed more appropriately.

  Each process of step S1040, step S1050, step S1060, step S1090, and step S1100 shown in FIG. 4 is omitted. When it is determined in step S1030 shown in FIG. 4 that the clutch load torque CL is equal to or lower than the base assist torque ATb (S1030: NO), the process of step S1080 is performed to calculate the clutch load torque CL in step S1020. The clutch load torque CL may be set as the updated base assist torque ATb. That is, the reduced clutch load torque CL may be set as it is as the updated base assist torque ATb. Even in this case, during the engagement of the clutch 12, it is possible to suppress an increase in the engine speed when an operation for reducing the actual clutch load torque is performed.

The upper limit value ATmax may be set based on one of the engine speed NE and the accelerator operation amount ACCP.
The limitation of the requested assist torque ATD by the upper limit value ATmax may be omitted. Even in this case, effects other than the above (5) to (7) can be obtained.

In the assist torque calculation process shown in FIG. 9, steps S4030 and S4040 may be omitted.
In the assist torque calculation process shown in FIG. 9, the gradual change value J is variably set. However, the gradual change value J may be set to a fixed value set as appropriate.

  The accelerator request torque ACCT is calculated based on the shift position SFT, the vehicle speed SP, and the accelerator operation amount ACCP. In addition, the accelerator request torque ACCT may be calculated based on the shift position SFT and the accelerator operation amount ACCP, or the accelerator request torque ACCT may be calculated based on the vehicle speed SP and the accelerator operation amount ACCP. Further, the accelerator required torque ACCT may be calculated based on another parameter different from the shift position SFT and the vehicle speed SP and the accelerator operation amount ACCP. More simply, the accelerator required torque ACCT may be calculated based only on the accelerator operation amount ACCP.

  The addition value of the accelerator request torque ACCT and the assist torque AT is set as the final request torque TF, but the accelerator request torque ACCT may not be added. Even in this case, effects other than the above (8) can be obtained.

In the above equation (2), an appropriate coefficient may be added in order to calculate the clutch load torque CL more accurately.
Although the smoothing process is performed on the basic shaft torque TEb, the smoothing process may be omitted and the basic shaft torque TEb may be used as it is as the engine shaft torque TE.

  -The degree of smoothing of the basic shaft torque TEb by the annealing process is made smaller during operation than when the accelerator pedal is not operated. In addition, more simply, the smoothing degree of the basic shaft torque TEb may be the same when the accelerator pedal is not operated and when the accelerator pedal is operated.

Although the basic shaft torque TEb is calculated based on the above formula (1), the calculation mode is an example, and the basic shaft torque TEb may be calculated in other modes.
Although the basic shaft torque TEb is estimated based on the engine operating state, it may be actually detected using a sensor or the like.

  DESCRIPTION OF SYMBOLS 10 ... Engine, 11 ... Crankshaft, 12 ... Clutch, 13 ... Clutch pedal, 14 ... Manual transmission, 15 ... Transmission input shaft, 16 ... Shift lever, 17 ... Control device, 20 ... Air flow meter, 21 ... Crank angle Sensors: 22 ... Water temperature sensor, 23 ... Accelerator sensor, 24 ... Vehicle speed sensor, 25 ... Shift sensor, 26U ... First clutch switch, 26L ... Second clutch switch, 30 ... Compressor, 31 ... Alternator.

Claims (5)

A device for controlling the output of an in-vehicle internal combustion engine whose output shaft is connected to a manual transmission via a clutch,
A clutch load torque, which is a load torque that resists rotation of the output shaft in the clutch engagement process, is calculated every predetermined period, and the assist torque of the engine output is updated based on the calculated clutch load torque. Torque assist control that increases the engine output according to the assist torque of
Of the output torque generated in the internal combustion engine, the clutch load torque is the torque transmitted to the clutch connected to the output shaft, the inertia mass of the internal combustion engine, and the clutch engagement process. Calculated based on the amount of change in engine speed,
Calculated when the calculated clutch load torque is equal to or less than the assist torque before the update and the deviation between the calculated clutch load torque and the assist torque before the update is greater than the first determination value set in advance. Set the clutch load torque as the updated assist torque,
The calculated clutch load torque is equal to or less than the assist torque before update, and the deviation is equal to or smaller than the first determination value and larger than the second determination value set to a value smaller than the first determination value. In some cases, the output control device for an internal combustion engine is characterized in that a value obtained by subtracting a predetermined amount from the assist torque before update is set as the assist torque after update. When the deviation is less than or equal to the second determination value, the assist torque before update is set as the assist torque after update.
The output control apparatus for an internal combustion engine according to claim 1 . An upper limit value of the assist torque is set based on the engine rotation speed and the accelerator operation amount. When the updated assist torque is larger than the upper limit value, the upper limit value is set as the updated assist torque.
The output control device for an internal combustion engine according to claim 1 or 2 . The upper limit is made smaller as the engine speed is higher.
The output control device for an internal combustion engine according to claim 3 . An accelerator demand torque that is a requested output torque of the engine in accordance with the accelerator operation amount is calculated, an added value of the accelerator demand torque and the updated assist torque is calculated as a final demand torque, and the final demand torque is calculated as the internal combustion engine. Output from
The output control device for an internal combustion engine according to any one of claims 1 to 4 .